identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
F1956C94AA834E13883896A779048B27.text	F1956C94AA834E13883896A779048B27.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma	<div><p>Genus Plectostoma</p><p>Plectostoma Adam 1865: 177. Type species: Plectostoma DeCrespignii (by original designation)</p><p>Geothauma Crosse 1892: 282. Type species (by original designation): Plectostoma grandispinosum (Godwin-Austen, 1889).</p><p>Generic classification dispute.</p><p>The genus Opisthostoma was described by Blanford and Blanford (1860) based on one species– Opisthostoma nilgiricum from India. Adam (1865b) described a second species of Opisthostoma, namely, Opisthostoma decrespignyi, which he previously described under the new genus Plectostoma (Adam 1865a). Nevertheless, Blanford (1867) concluded that the conchological differences between these two taxa were not enough to create a different genus. Instead, he suggested these could be two different subgenera. Next, another two subgenera– Gyrostropha Ancey, 1887 and Geothauma Crosse, 1892, were proposed for different forms of Opisthostoma and Plectostoma . However, Smith (1893a) suggested that this subgeneric classification was not necessary until more data other than shell morphology were available. Since then, a classification into three subgenera within the genus Opisthostoma, namely, Geothauma, Opisthostoma, and Plectostoma has generally been accepted (e.g. von Martens and Thiele 1908, van Benthem Jutting 1932, van Benthem Jutting 1952), until, in a recent review of the genus Opisthostoma, Vermeulen (1991, 1994) followed a classification into only two subgenera, namely, Opisthostoma and Plectostoma .</p><p>Diagnosis.</p><p>Despite the distinct ecological niche differences (see below–Distribution and habitat) between Opisthostoma and Plectostoma, it is not feasible to use this criterion in the genus identification, because information about the ecology is usually not available as most collections are made by soil sampling. After 150 years of work on Opisthostoma, it is still difficult to identify reliable apomorphic character states that can be used to distinguish between Opisthostoma and Plectostoma (Vermeulen 1991, 1994). Both share the character state of the constriction, which is a slight shrinkage in the whorl towards the end of the spire. When the animal retracts into its shell, its operculum rests at the constriction (Vermeulen 1991). It is, however, possible to make a morphological distinction between Opisthostoma and Plectostoma on the basic of the shell colouration in a fully grown adult, which is orange or pinkish in Plectostoma and white or pale yellowish in Opisthostoma . The colour differences between these two genera are very clear when comparing the living snails or freshly dead shell material (Figure 17, and Appendix 18). Some Plectostoma species have a regularly coiled tuba, and a shell form that is similar to Arinia . However, Plectostoma and Arinia can be easily distinguished by shell colour differences. The shell colour in Arinia is similar to that in Opisthostoma .</p><p>Description.</p><p>Apex. Protoconch is either slightly, moderately or distinctly convex (Figure 3).</p><p>Spire. Height: 1.0 mm– 3.7 mm. Width: 0.85 mm– 2.60 mm (Figure 11). Number of whorls between 2 3/4-71/4. Apical spire shape: oblong or depressed conical (Figure 4). Basal spire shape: conical, ovoid or ellipsoid (Figure 5). Whorl periphery: flat, slightly, moderately or distinctly convex. Umbilicus: open, partially closed, or totally closed.</p><p>Constriction. Parietal teeth: parietal side of inner constriction whorl (Figure 2) with two long lamellae (Figure 6A), two ridges with a knob at each end (Figure 6B), one ridge with a knob at one end (Figure 6C), or no teeth (Figure 6D). Basal teeth: basal side of inner constriction whorl (Figure 2) with no teeth (Figure 7B), one ridge running parallel with the whorl growing direction, one ridge with a knob at one end running perpendicular to the whorl growing direction, or a combination of the latter two types (Figure 7A).</p><p>Tuba. Coiling direction: regular coiling (type 1, Figure 8A) or distorted (Type 2, or 3) (Figure 8B and C). Tuba whorl length in proportion to spire last whorl: ca. 3/8-1 1/2. Proportion of tuba that attaches to spire: whole to none.</p><p>Aperture and peristome. Peristome: simple aperture without outer peristome (Figure 10B), or double peristome (Figure 10C and 10D). Shape of outer peristome (Figure 10A): same as inner peristome and uniformly round, or highly projected or slightly projected at either a particular side or at a several sides of anterior, poteriorior, left and right laterial (Figure 9 and 10A).</p><p>Spiral lines. Either thick or thin, or only thin lines present (Figure 12).</p><p>Radial ribs. Rib density: 4-32 per mm on the spire’s last whorl in right lateral view (Figure 13A). Intensity: thick or thin (Figure 13B). Shape: straight, slightly curved, distinctly curved, single humped, single looped or double looped and the shape remaining the same or changing between between the spire and the tuba (Figure 13C, but single-looped, and double-humped not shown). Inclination: from orthoclin to prosoclin.</p><p>Distribution and habitat.</p><p>The distribution range of Plectostoma is about 4.6 million square kilometres within the extent limited by 11°N, 97°E and 5°S, 120°E. However probably less than 5% of this large area is covered by limestone outcrops where suitable habitat may exist for obligate karst taxa like Plectostoma . The genus counts 79 species and occurs in Vietnam (1 species), Thailand (1), Peninsular Malaysia (28), Sumatra (1), and Borneo (48). Peninsular Malaysia, Sumatra and Borneo are part of the biogeographical region called Sundaland (Johnson 1964). Plectostoma is found on most limestone hills. However, the genus is conspicuously absent on the limestone hills to the west of the central mountain ranges, such as the hills in the States of Perak and Kedah in Peninsular Malaysia, and in the northwestern half of Sumatra (Figure 18). No species have been recorded from the east coast of Sumatra, where hardly any limestone outcrops exist.</p><p>Based on collection data and our field experience, there is a distinct ecological divergence between Plectostoma and Opisthostoma . This was already observed in the 19th century (Blanford and Blanford 1860, de Crespigny 1865, Blanford 1866), and also by Berry (1961). Plectostoma can only be found in limestone outcrops, where the rock face is its major habitat, although a few individuals can occasionally be found on vegetation debris below the limestone rock face. Opisthostoma, on the other hand, is a soil dweller, living in leaf litter on the forest floor. They are mostly but not exclusively found in forest over limestone bedrock (Schilthuizen et al. 2003b).</p><p>Phylogenetic relationships.</p><p>Our molecular phylogenetic analysis reveals that Plectostoma, Opisthostoma, and Arinia are phylogenetically closely related (Figure 16). It is important to point out that the phylogenetic relationships among Plectostoma, Opisthostoma (except Opisthostoma vermiculum), Opisthostoma vermiculum, and Arinia are unresolved. Figure 16 shows representative shell morphologies of the taxa that were included in the phylogenetic analysis, and it is clear that it is rather difficult to find shared derived characteristics (synapomorphies) in size, spire shape, or tuba coiling regime, for either Opisthostoma or Plectostoma .</p><p>Nonetheless, we treat Plectostoma and Opisthostoma as two separate genera based on their ecological divergence and differences in adult shell colouration. Similarly, we propose that Opisthostoma vermiculum and Arinia should be considered as two separate genera. However, this hypothesis needs further testing with more genetic data from Opisthostoma vermiculum Clements &amp; Vermeulen, 2008 (in Clements et al. 2008), the conchologically similar Opisthostoma gittenbergeri Vermeulen &amp; Clements, 2008 and further Arinia species.</p></div>	https://treatment.plazi.org/id/F1956C94AA834E13883896A779048B27	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
0E2EFF182AF60B9E969244C6085E4B0D.text	0E2EFF182AF60B9E969244C6085E4B0D.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma dindingensis	<div><p>Plectostoma dindingensis sp. n. Figure 19, Appendix 7</p><p>Type material.</p><p>Holotype: BOR 5642(1). Paratypes: BOR 5612(3)</p><p>Diagnosis.</p><p>Shares with Plectostoma mengaburensis and Plectostoma panhai the general shell form, in terms of apex, spire and tuba, but differs by lacking constriction teeth and having a more tightly coiled tuba (less than 1/4 of the tuba visible in top view).</p><p>Etymology.</p><p>This species is named after its type locality–Dinding .</p><p>Description.</p><p>Apex. Shape: moderately convex.</p><p>Spire. Height: 1.8-1.9 mm. Width: 1.4-1.5 mm. Number of whorls: 3 7/8-4 5/8. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: distinctly convex. Umbilicus: partially closed by tuba.</p><p>Constriction . Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 1 and aperture visible from back view. Tuba whorl length in proportion to spire last whorl: ca. 5/8-3/4. Proportion of tuba that attaches to the spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 6-8 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. The exact location is unknown. The specimens are labeled as collected from “dinding” . It could be near Kampung Bukit Dinding, Pahang (3°49'41"N, 102°22'3"E).</p><p>Distribution range. The species has only been recorded from the type locality (Figure 18D).</p><p>Conservation status.</p><p>Vulnerable (D2 ver. 10.1). The samples was collected from a living population in 1997. The population status remains unclear. The area around Kampung Bukit Dinding has been converted to plantation and no significant undisturbed forest coverage remains.</p><p>Discussion.</p><p>See discussion under Plectostoma christae .</p></div>	https://treatment.plazi.org/id/0E2EFF182AF60B9E969244C6085E4B0D	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
EF57DB94C3BD90EB1674F500E83DA143.text	EF57DB94C3BD90EB1674F500E83DA143.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma mengaburensis	<div><p>Plectostoma mengaburensis sp. n. Figures 17E, 20, Appendix 7</p><p>Type material.</p><p>Holotype: BOR 5643(1). Paratypes: BOR 5574(&gt;25), V8822 (6)</p><p>Diagnosis.</p><p>Shares with Plectostoma dindingensis and Plectostoma panhai the general shell form, in the terms of apex, spire and tuba, but differs by lacking constriction teeth and having a less tightly coiled tuba (more than 1/4 of the tuba visible in top view).</p><p>Etymology.</p><p>This species is named after its type locality–Mengabur .</p><p>Description.</p><p>Apex. Shape: moderately convex.</p><p>Spire. Height: 1.9-2.2 mm. Width: 1.4-1.6 mm. Number of whorls: 3 7/8-4 1/2. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: distinctly convex. Umbilicus: open or half of the umbilicus closed by tuba.</p><p>Constriction. Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 1 and aperture visible from back view. Tuba whorl length in proportion to spire last whorl: ca. 5/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 7 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. An unnamed small limestone hill in the plantation near the large Bukit Mengabur quarry (3°43'50"N, 102°49'40"E).</p><p>Distribution range. This species only occurs in the Mengabur limestone cluster (Figure 18D).</p><p>Conservation status.</p><p>Near Threatened. This species only occurs in the Mengabur limestone cluster, which is quite large (ca. 10 km2, estimated from Google Earth), and its vegetation cover is largely undisturbed. However, quarrying activities have started at the eastern part of the cluster and the whole limestone cluster is surrounded by plantation.</p><p>Discussion.</p><p>See discussion under Plectostoma christae .</p></div>	https://treatment.plazi.org/id/EF57DB94C3BD90EB1674F500E83DA143	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
6C131BFB0495BBC8A5B9AFA80B9CED57.text	6C131BFB0495BBC8A5B9AFA80B9CED57.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma sinyumensis (Maassen 2001) Maassen 2001	<div><p>Plectostoma sinyumensis (Maassen, 2001) Figures 17L, 21, Appendix 7</p><p>Opisthostoma sinyumensis Maassen, 2001: 52, figures 1, 6 &amp; 7 (original description).</p><p>Opisthostoma sinyumensis Maassen, Clements (2007: 74).</p><p>Opisthostoma sinyumensis Maassen, Clements et al. (2008: 2760).</p><p>Opisthostoma sinyumensis Maassen, Webster et al. (2012: 628).</p><p>Type material.</p><p>Holotype: ZMA 138439(1) (Seen). Paratypes: ZMA 138440(&gt;25) (Seen), RMNH 81804(2) (Seen).</p><p>Other examined materials.</p><p>BOR 462(5), BOR 5537(&gt;10), BOR 5623(&gt;50).</p><p>Diagnosis .</p><p>Shares with Plectostoma dindingensis, Plectostoma mengaburensis, Plectostoma christae, and Plectostoma panhai the general shell form, in terms of apex, apical spire and tuba, but differs by having an ellipsoid basal spire.</p><p>Description.</p><p>Apex. Shape: moderately convex.</p><p>Spire. Height: 1.6-1.9 mm. Width: 1.2-1.3 mm. Number of whorls: 3-3 3/4. Apical spire shape: depressed conical. Basal spire shape: ellipsoid. Whorl periphery: distinctly convex. Umbilicus: almost completely closed by tuba.</p><p>Constriction. Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 1 and aperture visible between right lateral and back view. Tuba whorl length in proportion to spire last whorl: ca. 5/8-3/4. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 9-10 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Gunung Senyum, Pahang (3°42'35"N, 102°26'3"E).</p><p>Distribution range. In addition to the type locality, this species also was found at the Jebak Puyuh limestone outcrop, which lies about 1 km east of Gunung Senyum (Figure 18D). BOR 462 was collected in Pulau Singa Besar, which is located about 300 km from type locality. The reliability of the collection data is dubious (the same was found for BOR 463 of Plectostoma relauensis).</p><p>Conservation status.</p><p>Near Threatened. There are four limestone hills in this cluster. Gunung Senyum and Jebak Puyuh are the larger among these four hills. The former is gazetted as recreation forest but the latter has been at risk of destruction. Jebak Puyuh had been earmarked for quarrying several years ago, but the plan has been abandoned. Plectostoma sinyumensis has been recorded from these two hills, but its status at the two smaller hills remains unknown. In a survey in July 2010, a living population was recorded at Jebak Puyuh, in an enclosed humid sinkhole. Intensive surveying on the limestone rock faces of Gunung Senyum and other parts of Jebak Puyuh has failed to retrieve any additional living individuals, probably because most of the rock faces were very dry.</p><p>Discussion.</p><p>See discussion under Plectostoma christae .</p></div>	https://treatment.plazi.org/id/6C131BFB0495BBC8A5B9AFA80B9CED57	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
1BE68043C78E2020642B8CFD8ACA7EDE.text	1BE68043C78E2020642B8CFD8ACA7EDE.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma umbilicatum (van Benthem Jutting 1952) van Benthem Jutting 1952	<div><p>Plectostoma umbilicatum (van Benthem Jutting, 1952) Figure 17B, 22, Appendix 8</p><p>Opisthostoma umbilicatum van Benthem Jutting, 1952: 49, figure 25 (original description).</p><p>Opisthostoma umbilicatum van Benthem Jutting, van Benthem Jutting (1961: 39).</p><p>Opisthostoma umbilicatum van Benthem Jutting, Clements (2007: 74).</p><p>Opisthostoma umbilicatum van Benthem Jutting, Clements et al. (2008: 2760).</p><p>Type material.</p><p>Holotype: ZMA 136070(1) (Seen). Paratypes: ZMA 136071(8) (Seen).</p><p>Other examined materials.</p><p>BOR 5503(&gt;10), BOR 5625(&gt;25).</p><p>Diagnosis.</p><p>Shares with Plectostoma dindingensis, Plectostoma mengaburensis, and Plectostoma panhai the tuba form, but differs by having an oblong conical apical spire.</p><p>Description.</p><p>Apex. Shape: moderately convex.</p><p>Spire. Height: 2.0-2.3 mm. Width: 1.3-1.5 mm. Number of whorls: 4 5/8-4 3/8. Apical spire shape: oblong conical. Basal spire shape: ovoid. Whorl periphery: distinctly convex. Umbilicus: completely open or partially closed by tuba.</p><p>Constriction. Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 1 and aperture visible from back view. Tuba whorl length in proportion to spire last whorl: ca. 1/2-3/4. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 6-9 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Limestone hill cluster named Kota Tongkat (3°53'28"N, 102°28'23"E).</p><p>Distribution range. It is only known from the type locality. All other adjacent limestone outcrops have been sampled, but only other Plectostoma species were found (Figure 18D).</p><p>Conservation status.</p><p>Critically Endangered (B2ab(iii)+C2a(i) ver. 10.1). The Kota Tongkat limestone cluster is surrounded by oil palm plantation and heavily degraded forest . This species is only known from this limestone cluster. Recent soil samplings have not revealed any recent dead shells (Clements et al. 2008). Neverthelss, we found a living population with fewer than 100 individuals at a wet stalagmite of the entrance of one the caves during an intensive survey in May 2011. During that survey, we noticed that all other rock surfaces of the limestone outcrops in Kota Tongkat were very dry. Thus, the recorded and other unknown living populations are at risk of extinction because a long drought might wipe them out.</p><p>Discussion.</p><p>See discussion under Plectostoma christae .</p></div>	https://treatment.plazi.org/id/1BE68043C78E2020642B8CFD8ACA7EDE	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
D7BAA3FBD58EA8EB6AB5D1D0BD61581B.text	D7BAA3FBD58EA8EB6AB5D1D0BD61581B.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma siphonostomum (van Benthem Jutting 1952) van Benthem Jutting 1952	<div><p>Plectostoma siphonostomum (van Benthem Jutting, 1952) Figure 17N, 23, Appendix 8</p><p>Opisthostoma siphonostomum van Benthem Jutting, 1952: 52, figure 27 (original description).</p><p>Opisthostoma siphonostomum van Benthem Jutting, van Benthem Jutting (1961: 39).</p><p>Opisthostoma siphonostomum van Benthem Jutting, Berry (1964: 203).</p><p>Type material.</p><p>Holotype: ZMA 136054(1) (Seen). Paratype: ZMA 136055(8) (Seen).</p><p>Other examined materials.</p><p>ZMA 162138(&gt;100), BOR 5513 (&gt;25), BOR 5521(&gt;10), BOR 5557(&gt;10), V 8199(&gt;50), V 8223(&gt;25).</p><p>Diagnosis.</p><p>Shares with Plectostoma christae the tuba form, but differs by having an oblong conical apical and conical basal spire.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 1.9-2.1 mm. Width: 1.2-1.5 mm. Number of whorls: 4 3/4-5. Apical spire shape: oblong conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: Open.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 1 and aperture visible between right lateral and back view. Tuba whorl length in proportion to spire last whorl: ca. 3/8-1/2. Proportion of tuba that attaches to spire: at least 1/2.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 7-8 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Gua Siput, Taman Negara, Pahang (4°26'47"N, 102°14'44"E).</p><p>Distribution range. Plectostoma siphonostomum has a similar distribution pattern as Plectostoma salpidomon and often occurs sympatrically with that species. It can be found in many limestone outcrops in the valley between the Titingwangsa Range, Tahan Range and Benom Range (Figure 18D).</p><p>Conservation status.</p><p>Least concern. Living populations of Plectostoma siphonostomum were recorded at several limestone hills during surveys between 2010 and 2011. Several of these are located within the National Park.</p><p>Discussion.</p><p>See discussion under Plectostoma christae .</p></div>	https://treatment.plazi.org/id/D7BAA3FBD58EA8EB6AB5D1D0BD61581B	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
C04BFE6AD58458D838688FB7450FC29B.text	C04BFE6AD58458D838688FB7450FC29B.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma panhai (Maassen 2001) Maassen 2001	<div><p>Plectostoma panhai (Maassen, 2001) Figure 24, Appendix 7</p><p>Arinia panhai Maassen, 2001: 55, figure 4, 12 &amp; 13 (original description).</p><p>Type material.</p><p>Holotype: RMNH 81809(1) (Seen). Paratypes: RMNH 81810(2) (Seen).</p><p>Other examined materials.</p><p>ZMA 138438(1).</p><p>Diagnosis.</p><p>Shares with Plectostoma mengaburensis and Plectostoma dindingensis the general shell form, in the terms of apex, spire and tuba, but differs by having a single parietal constriction tooth.</p><p>Description.</p><p>Apex. Shape: moderately convex.</p><p>Spire. Height: 2.1-2.2 mm. Width: 1.6-1.7 mm. Number of whorls: 4 1/2-4 5/8. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately convex. Umbilicus: open.</p><p>Constriction . Parietal teeth: one. Basal teeth: none.</p><p>Tuba. Coiling direction: type 1 and aperture visible from back view. Tuba whorl length in proportion to spire last whorl: ca. 3/4. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 8-9 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Tham Krachaeng, Thailand (6°12'50"N, 101°12'9"E). The location description in the original publication is not completely correct "(06°55'022"N, 101°12'160"E)" (Maassen 2001).</p><p>Distribution range. This species is only known from the type locality (Figure 18D).</p><p>Conservation status.</p><p>Data Deficient.</p><p>Discussion.</p><p>See discussion under Plectostoma christae .</p></div>	https://treatment.plazi.org/id/C04BFE6AD58458D838688FB7450FC29B	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
C3E398FF662DAAC2BA8F2373C29D1936.text	C3E398FF662DAAC2BA8F2373C29D1936.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma christae (Maassen 2001) Maassen 2001	<div><p>Plectostoma christae (Maassen, 2001) Figures 17Q, 25, Appendix 6</p><p>Opisthostoma christae Maassen, 2001: 52, figures 3, 10 &amp; 11 (original description).</p><p>Opisthostoma jensi Maassen, 2001: 56, figures 5, 14 &amp; 15 (original description), syn. n.</p><p>Type material.</p><p>Holotype: RMNH 81805(1) (Seen). Paratypes: RMNH 81806(1) (Seen).</p><p>Other examined materials.</p><p>RMNH 81807(1), RMNH 81808(1), ZMA 138436(1), ZMA 138437(2), BOR 3496(1), BOR 5505(&gt;25), BOR 5506(&gt;50), BOR 5509(&gt;25), BOR 5572(2), V 12702(1), V 8314(&gt;25), V 8406(2), V 9153(2), V 9207(&gt;100), V 9285(3).</p><p>Diagnosis.</p><p>Shares with Plectostoma dindingensis, Plectostoma mengaburensis, and Plectostoma panhai the general shell spire form but differs by having two parietal constriction teeth and aperture visible when shell observed in left lateral view.</p><p>Description.</p><p>Apex. Shape: moderately convex.</p><p>Spire. Height: 1.9-2.6 mm. Width: 1.4-1.8 mm. Number of whorls: 3 5/8-4 1/2. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 1 and aperture visible from left lateral view. Tuba whorl length in proportion to spire last whorl: ca. 3/8-5/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 5-6 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Limestone hills, 16 km west of Gua Musang (4°54'46"N, 102°6'22"E).</p><p>Distribution range. Limestone hills along the 50 km Northeast transect between 4°38'51"N, 101°58'58"E and 5°0'13"N, 102°11'59"E (Figure 18D).</p><p>Conservation status.</p><p>Near Threatened. Until today, this species has been recorded from at least six limestone hills. In a field survey in 2011 and 2012, living populations of Plectostoma christae could be found on four of these hills. All of these are located near the road and are surrounded by oil palm plantation, although there is no immediate threat.</p><p>Discussion.</p><p>Plectostoma christae, together with Plectostoma dindingensis, Plectostoma mengaburensis, Plectostoma sinyumensis, Plectostoma umbilicatum, Plectostoma siphonostomum, and Plectostoma panhai represent a group of Plectostoma species that have a regulary coiled tuba (type 1 tuba). The species of this group occur only in Peninsular Malaysia and are genetically highly divergent (&gt; 10% differences in COI) from the others (Table 4). All of the seven species are distributed allopatrically (Figure 18D).</p><p>We synonymised Plectostoma jensi with Plectostoma christae, both of which were described from the same locality. Maassen (2001) distinguished between them by the slight difference in umbilicus opening and aperture tilting. In the material at our disposal, we recognised that these differences are intrapopulational variation. All individuals share the same diagnostic shell characters as mentioned above. In addition to the morphological evidence, the genetic variation between individuals with different shell forms is smaller than our species delimitation threshold of 10%.</p><p>Two species of this group, namely Plectostoma christae and Plectostoma siphonostomum, have a wider distribution range than other species in this group. The two species occur parapatrically on the limestone hills in the centre of Peninsular Malaysia (Figure 18D). On the other hand, very little is known of the distribution range of Plectostoma panhai . Although this species was reported only once and only from the type locality, it might also occur at other limestone sites near the type locality. Plectostoma panhai is very similar to Plectostoma christae, but the two are separated by more than 150 km, and the limestone hills in between are occupied by three other Plectostoma species. The disjunct distribution and its single constriction tooth support the decision that Plectostoma panhai is a distinct species from Plectostoma christae .</p><p>The remaining four species of this group, namely, Plectostoma sinyumensis, Plectostoma mengaburensis, Plectostoma dindingensis, and Plectostoma umbilicatum, are site endemics, occurring at each of the four small limestone clusters in the centre of Peninsular Malaysia (Figure 18D). These clusters are each quite isolated, with no other limestone hills within a 20 km radius.</p><p>Although these four species occur in adjacent limestone limestone clusters, and they have similar shell shapes, their taxonomic status are clear. The COI sequence divergence between these species is larger than 13% and each of them has a set of diagnostic shell characters (Tables 3 and 4). This may raise the question how each species evolved in each limestone cluster and how long these four species have been isolated. For example, a neighbouring species, Plectostoma salpidomon, has a similar distribution range as the former four species, but the morphological and genetic divergence is much smaller than in these four species. Presumably, the answer lies in the details of the geomorphological evolution of the limestone outcrops, which, however, remains largely unknown.</p></div>	https://treatment.plazi.org/id/C3E398FF662DAAC2BA8F2373C29D1936	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
E573215260DDCD0E978CA9341D22D75B.text	E573215260DDCD0E978CA9341D22D75B.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma crassipupa (van Benthem Jutting 1952) van Benthem Jutting 1952	<div><p>Plectostoma crassipupa (van Benthem Jutting, 1952) Figures 17I, M, 26, Appendix 6</p><p>Opisthostoma crassipupa van Benthem Jutting, 1952: 51, figure 26 (original description).</p><p>Opisthostoma crassipupa van Benthem Jutting, van Benthem Jutting (1961: 39).</p><p>Opisthostoma crassipupa van Benthem Jutting, Clements (2007: 74).</p><p>Opisthostoma crassipupa van Benthem Jutting, Clements et al. (2008: 2760).</p><p>Type material.</p><p>Holotype: ZMA 135994(1) (Seen). Paratype: ZMA 135993(&gt;50) (Seen).</p><p>Other examined materials.</p><p>BOR 5512(&gt;50), BOR 5515(2), BOR 5624(&gt;10), BOR 5629(3), V 8392(&gt;10), V 8407(10), V 8408(4), V 8437(&gt;10), V 8898(7). V 8912(1), V 8956(1), V 9097(9), V 9157(&gt;10), V 9326(&gt;10), V 9353(3), V 9366(10).</p><p>Genetic distance between BOR 5512 and BOR 5515 is 14%.</p><p>Diagnosis.</p><p>Shares with Plectostoma sciaphilum, Plectostoma senex, and Plectostoma turriforme the tuba form, but differs by having a slightly or moderately convex apex and depressed apical spire.</p><p>Description.</p><p>Apex. Shape: slightly or moderately convex.</p><p>Spire. Height: 1.3-3.0 mm. Width: 1.2-1.4 mm. Number of whorls: 3 1/2-4 1/2. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately or distinctly convex. Umbilicus: closed by tuba (common) or partially open (rare).</p><p>Constriction. Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 3 and aperture visible from left lateral view. Tuba whorl length in proportion to spire last whorl: ca. 1/2-3/4 Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 6-8 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: moderately prosoclin.</p><p>Distribution.</p><p>Type locality. Gua Musang (4°52'59"N, 101°58'12"E).</p><p>Distribution range. This species mainly occurs in the limestome hills that are located between Gua Musang and as far as 30 km radius of Gua Musang. One populations exists at a limestone hill that is located about 90 km north of Gua Musang (Figure 18A).</p><p>Conservation status.</p><p>Least Concern. Almost all the limestone hills are located along main roads and/or surrounded by oil palm plantation or cleared for urban development. However, several large limestone hills that hold the species are located in the well-protected National Park (Taman Negara), State of Pahang, Malaysia.</p><p>Discussion.</p><p>The species is well-characterised, although it displays considerable variability in the shell shape (Appendix 6).</p></div>	https://treatment.plazi.org/id/E573215260DDCD0E978CA9341D22D75B	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
368D5AC904DDED99352DFEA28B202EAB.text	368D5AC904DDED99352DFEA28B202EAB.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma tonkinianum (Dautzenberg & Fischer 1905) Dautzenberg & Fischer 1905	<div><p>Plectostoma tonkinianum (Dautzenberg &amp; Fischer, 1905) Figure 27, Appendix 8</p><p>Opisthostoma tonkinianum Dautzenberg &amp; Fischer, 1905: 444, plate 10 - figure 5, 6 and 7 (original description).</p><p>Opisthostoma tonkinianum Dautzenberg &amp; Fischer, Saurin (1953: 134).</p><p>Opisthostoma tonkinianum Dautzenberg &amp; Fischer, van Benthem Jutting (1962: 12).</p><p>Opisthostoma tonkinianum Dautzenberg &amp; Fischer, Fischer (1963: 34).</p><p>Type material.</p><p>Not seen.</p><p>Other examined materials.</p><p>ZMA 162136(1), V 10000(&gt;25), V 10010(&gt;25), V 10022(&gt;25), V 11243(&gt;25), V 11270(&gt;25), V 11432(3), V 11502(&gt;50), V 7937(5), V 9940(&gt;10), V 9957(&gt;25).</p><p>Diagnosis.</p><p>Shares with Plectostoma whitteni the general shell form, in terms of apex, spire and tuba, but differs by having two lamella-shaped constriction teeth and a higher spire (&gt; 3 mm).</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 3.1-3.8 mm. Width: 2.4-2.6 mm. Number of whorls: 4 3/4-4 7/8. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: distinctly convex. Umbilicus: completely closed by tuba.</p><p>Constriction. Parietal teeth: two lamellae. Basal teeth: none.</p><p>Tuba. Coiling direction: type 3 and aperture visible in left lateral view. Tuba whorl length in proportion to spire last whorl: ca. 5/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: simple peristome.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 6-7 ribs per mm. Rib intensity: thin. Shape: slightly curved to single-humped. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. “Tonkin” (Dautzenberg and Fischer 1905). The exact locality should be the limestone hill near Chau Dao.</p><p>Distribution range. Limestone hills in the Province of Kien Giang (Figure 18A).</p><p>Conservation status.</p><p>Data deficient. Some recent dead shells have been collected but no information is available on the habitat and population status.</p><p>Discussion.</p><p>In recent years, this species has been recorded at several limestone hills in the vicinity of Ha Tien, which is a popular tourism site. Although the type specimen cannot be located and the exact type locality cannot be determined, the shell morphology of the recent material fits well with the description in the original publication.</p><p>In the original publication, Dautzenberg and Fischer (1905) mentioned that this species was collected by M. Mansuy from Tonkin (French protectorate), which was a large area that included part of Southern China, and the Northern parts of Laos and Vietnam. Dautzenberg and Fischer (1905) further provided a list of locations where most of the snails were collected. One of these was, Chau Doc, which is located about 70 km from Ha Tien. Furthermore, a recent intensive land snail survey in the Northern Provinces of Laos, namely, Hua Phan and Luang Prabang, did not discover any Plectostoma species (Muratov and Abdou 2006). Hence, Plectostoma tonkinianum probably occurs in the small limestone hill cluster in the coastal area of the Southern part of Vietnam and neighboring Cambodia.</p></div>	https://treatment.plazi.org/id/368D5AC904DDED99352DFEA28B202EAB	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
307342CA97B1DEAD2EDDC2A561384113.text	307342CA97B1DEAD2EDDC2A561384113.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma whitteni	<div><p>Plectostoma whitteni sp. n. Figures 17G, 28, Appendix 8</p><p>Type material.</p><p>Holotype: BOR 5644(1). Paratypes: BOR 5536(&gt;10), V 8802(1), V 8885(&gt;10).</p><p>Diagnosis.</p><p>Shares with Plectostoma tonkinianum the general shell form, in the terms of apex, spire and tuba, but differs by lacking constriction teeth and lower spire (&lt;2 mm).</p><p>Etymology.</p><p>This species is named after Dr. Tony Whitten, who was senior biodiversity specialist of the World Bank between 1995 and 2010, and is currently the Regional Director for Asia-Pacific Fauna &amp; Flora International. Dr. Whitten has been actively promoting the protection of the biodiversity that is associated with limestone and has been involved in conservation action to protect limestone habitats.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 1.7-1.9 mm. Width: 1.4-1.6 mm. Number of whorls: 3 7/8-4 1/4. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: distinctly convex. Umbilicus: completely closed by tuba.</p><p>Constriction. Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 3 and aperture visible in left lateral view. Tuba whorl length in proportion to spire last whorl: ca. 1/2-5/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 6-7 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Gua Taat, Tasik Kenyir (4°51'3"N, 102°43'21"E).</p><p>Distribution range. This species only occurs in Gua Taat, Tasik Kenyir (Figure 18A).</p><p>Conservation status.</p><p>Least Concern. Gua Taat is located in a prioritised protected National Park with good forest cover.</p><p>Discussion.</p><p>The general shell form of Plectostoma whitteni is similar to Plectostoma tonkinianum . There is no genetic information for Plectostoma tonkinianum, but Plectostoma whitteni is genetically closer to Plectostoma tohchinyawi than to any of the other 18 species. Nevertheless, Plectostoma whitteni is considered a distinct species as compared to Plectostoma tonkinianum and Plectostoma tohchinyawi because of the lack of constriction teeth.</p></div>	https://treatment.plazi.org/id/307342CA97B1DEAD2EDDC2A561384113	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
C0E1BB78FE859889D28375353F2B924E.text	C0E1BB78FE859889D28375353F2B924E.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma sciaphilum (van Benthem Jutting 1952) van Benthem Jutting 1952	<div><p>Plectostoma sciaphilum (van Benthem Jutting, 1952) Figure 29, Appendix 7</p><p>Opisthostoma sciaphilum van Benthem Jutting, 1952: 45, figure 23 (original description).</p><p>Type material.</p><p>Holotype: ZMA 136049(1) (Seen). Paratypes: ZMA 136050(&gt;10) (Seen).</p><p>Diagnosis.</p><p>Shares with Plectostoma senex and Plectostoma turriforme the tuba form, but differs by lacking basal constriction teeth.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 2.6-2.9 mm. Width: 1.5-1.6 mm. Number of whorls: 4 1/4-5 1/2. Apical spire shape: oblong conical. Basal spire shape: ovoid. Whorl periphery: distinctly convex. Umbilicus: completely closed by tuba.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 3 and aperture visible in left lateral view. Tuba whorl length in proportion to spire last whorl: ca. 3/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 6-8 ribs per mm. Rib intensity: thin. Shape: slightly curved.</p><p>Distribution.</p><p>Type locality. Bukit Panching, Pahang (3°53'28"N, 103°8'26"E).</p><p>Distribution range. Endemic to Bukit Panching (not seen in Figure 18A because its symbol overlaps with Plectostoma senex).</p><p>Conservation status.</p><p>Extinct. Its only habitat–Bukit Panching, has been completed quarried away (see also Schilthuizen and Clements 2008). The ruin is now inundated. The status of this species in a previous assessment (IUCN redlist) was: Critically Endangered B2ab(ii,iii) ver. 3.1 (Clements 2009a).</p><p>Discussion.</p><p>See under Plectostoma turriforme .</p></div>	https://treatment.plazi.org/id/C0E1BB78FE859889D28375353F2B924E	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
BC7AE61FB9D97AA5F02C73E6CF107B80.text	BC7AE61FB9D97AA5F02C73E6CF107B80.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma senex (van Benthem Jutting 1952) van Benthem Jutting 1952	<div><p>Plectostoma senex (van Benthem Jutting, 1952) Figures 17H, 30, Appendix 7</p><p>Opisthostoma senex van Benthem Jutting, 1952: 47, figure 24 (original description).</p><p>Type material.</p><p>Holotype: ZMA 136052(1) (Seen). Paratypes: ZMA 136053(&gt;10) (Seen).</p><p>Other examined materials.</p><p>RMNH 44723(5), BOR 460(1), BOR 5575(3), BOR 5603(2), BOR 5628(&gt;100), BOR 5631(&gt;10), V 5117(9).</p><p>Diagnosis.</p><p>Shares with Plectostoma sciaphilum and Plectostoma turriforme the tuba form, but differs by having two knob-shaped constriction teeth and fewer than 6 whorls.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 2.6-3.1 mm. Width: 1.6-1.7 mm. Number of whorls: 5 1/8-5 5/8. Apical spire shape: oblong conical. Basal spire shape: ovoid. Whorl periphery: moderately to distinctly convex. Umbilicus: completely closed by tuba.</p><p>Constriction. Parietal teeth: two. Basal teeth: one transverse tooth.</p><p>Tuba. Coiling direction: type 3 and aperture visible in left lateral view. Tuba whorl length in proportion to spire last whorl: ca. 3/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 4 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Gua Charas, limestone hill near Sungai Lembing in the state of Pahang, Malaysia (3°54'27"N, 103°8'47"E).</p><p>Distribution range. In addition to the type locality, this species had been recorded from Bukit Panching (Figure 18A).</p><p>Conservation status.</p><p>Critically Endangered (B2ab(iii)+C2a(i) ver. 10.1). This species is known from two locations. One of these, Bukit Panching, does not exist anymore. Two intensive surveys at the other location, Bukit Charas, were conducted in Feb. 2010 and May 2011. Two living populations with fewer than 50 individuals were found at wet staglamites near the cave. No other living population was found elsewhere on Bukit Charas. The status of this species in a previous assessment (IUCN redlist) was: vulnerable D2 ver. 3.1 (Clements 2009b).</p><p>Discussion.</p><p>See discussion under Plectostoma turriforme .</p></div>	https://treatment.plazi.org/id/BC7AE61FB9D97AA5F02C73E6CF107B80	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
833DD0C1B007C492AFC16F0D21043D01.text	833DD0C1B007C492AFC16F0D21043D01.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma turriforme (van Benthem Jutting 1952) van Benthem Jutting 1952	<div><p>Plectostoma turriforme (van Benthem Jutting, 1952) Figure 31, Appendix 8</p><p>Opisthostoma turriforme van Benthem Jutting, 1952: 43, figure 22 (original description).</p><p>Type material.</p><p>Holotype: ZMA 136068(1) (Seen). Paratypes: ZMA 136069(&gt;10) (Seen).</p><p>Other examined materials.</p><p>BOR 461(2), BOR 5609(2).</p><p>Diagnosis.</p><p>Shares with Plectostoma sciaphilum and Plectostoma senex the tuba form, but differs by having two lamella-shaped constriction teeth and having more than 6 whorls.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 3.2 mm. Width: 1.6 mm. Number of whorls: 7. Apical spire shape: oblong conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: completely closed by tuba.</p><p>Constriction. Parietal teeth: two. Basal teeth: two.</p><p>Tuba. Coiling direction: type 3 and aperture visible in left lateral view. Tuba whorl length in proportion to spire last whorl: ca. 3/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 5 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Bukit Tenggek, Pahang (4°0'51"N, 103°9'34"E).</p><p>Distribution range. In addition to the type locality, this species can be found at nearby Bukit Sagu (Figure 18A).</p><p>Conservation status.</p><p>Critically Endangered (B2ab(iii)+C2a(i) ver. 10.1). The whole Bukit Tenggek will disappear by 2014 because of quarrying activity. Moreover, more than half of Bukit Sagu has already been quarried away (see also Schilthuizen and Clements 2008). Although living individuals had been recorded from Bukit Sagu in 1997 (BOR 5609), neither living nor recently dead individuals were found in a recent survey conducted in 2010 and 2011.</p><p>Discussion.</p><p>Plectostoma turriforme, Plectostoma sciaphilum, and Plectostoma senex are three very similar species than occur in the four lenticular easternmost limestone hills in Peninsular Malaysia (Figure 18A). These four hills, namely, Bukit Panching, Bukit Charas, Bukit Sagu, and Bukit Tenggek are located along a 15 km longitudinal transect. Plectostoma turriforme occurs at the two former sites and Plectostoma senex at the two latter sites. Plectostoma sciaphilum occurs sympatrically with Plectostoma turriforme in Bukit Panching. These four hills (and thus the three species) are among the most isolated limestone outcrops in Peninsular Malaysia.</p></div>	https://treatment.plazi.org/id/833DD0C1B007C492AFC16F0D21043D01	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
F91AD6E4755B9C83932314E8DB6B01DB.text	F91AD6E4755B9C83932314E8DB6B01DB.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma palinhelix (van Benthem Jutting 1952) van Benthem Jutting 1952	<div><p>Plectostoma palinhelix (van Benthem Jutting, 1952) Figures 17C, 32, Appendix 12</p><p>Opisthostoma palinhelix van Benthem Jutting, 1952: 40, figure 20 (original description).</p><p>Type material.</p><p>Holotype: ZMA 136030(1) (Seen). Paratype: ZMA 136031(&gt;10) (Seen).</p><p>Other examined materials.</p><p>BOR 466(1), BOR 5520(5), V 5104(5).</p><p>Diagnosis.</p><p>Shares with Plectostoma retrovertens the spire and tuba form, but differs by having spire height between 1.6-1.9 mm.</p><p>Description.</p><p>Apex. Shape: slightly convex.</p><p>Spire. Height: 1.6-1.9 mm. Width: 1.1-1.3 mm. Number of whorls: 3 3/4-4 1/4. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately to distinctly convex. Umbilicus: partially or completely closed by tuba.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible between right lateral and back view; the tuba coils upward until the first teleconch whorl of the spire. Tuba whorl length similar to that of the last whorl of the spire. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similer to inner peristome, projected all around, except the posterior part, where the two lateral sides are slightly more projected than the anterior side.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 7-8 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Bukit Serdam, Pahang (3°49'47"N, 101°55'36"E).</p><p>Distribution range. To date, this species has been recorded from three limestone hills, namely Bukit Serdam, Gua Kechil and a small hill nearby (Figure 18C).</p><p>Conservation status.</p><p>Vulnerable (B2ab(iii) ver. 10.1). There are four limestone hills in this area, of which Bukit Serdam and its next unnamed hill support populations (assessment done in 2010 and 2011). Two of the hills, namely, Bukit Serdam and Gunung Panas, are now being quarried. The smallest unnamed hill is highly degraded and Gua Kechil is surrounded by oil palm plantation.</p><p>Discussion.</p><p>See discussion under Plectostoma retrovertens .</p></div>	https://treatment.plazi.org/id/F91AD6E4755B9C83932314E8DB6B01DB	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
A2D51D045BA52515849E8C1BE65CD31D.text	A2D51D045BA52515849E8C1BE65CD31D.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma retrovertens (Tomlin 1938) Tomlin 1938	<div><p>Plectostoma retrovertens (Tomlin, 1938) Figures 17R, 33, Appendix 13</p><p>Opisthostoma retrovertens Tomlin, 1938: 73, Plate 2 - figure 3 (original description).</p><p>Opisthostoma retrovertens Tomlin, van Benthem Jutting (1952: 39).</p><p>Opisthostoma retrovertens Tomlin, Berry (1961).</p><p>Opisthostoma retrovertens Tomlin, Berry (1962).</p><p>Opisthostoma retrovertens Tomlin, Berry (1963).</p><p>Opisthostoma retrovertens Tomlin, Berry (1964).</p><p>Opisthostoma retrovertens Tomlin, Berry (1966).</p><p>Opisthostoma retrovertens Tomlin, Solem (1966).</p><p>Opisthostoma retrovertens Tomlin, Illert (1987: 800, figure 2a).</p><p>Opisthostoma retrovertens Tomlin, Solem and Solem (1976: 31).</p><p>Opisthostoma retrovertens Tomlin, Heller (2001: 426).</p><p>Opisthostoma retrovertens Tomlin, Clements (2007: 74).</p><p>Opisthostoma retrovertens Tomlin, Clements et al. (2008: 2760).</p><p>Type material.</p><p>Holotype: BMNH 1938.10.25.2(1) (Seen). Paratype: ZMA 136044(&gt;10) (Seen).</p><p>Other examined materials.</p><p>RMNH 244699(1), RMNH 44725(8), ZMA 162133(&gt;10), ZMA 162148(8), BOR 5559(3), BOR 5621(9), V 5124(9).</p><p>Diagnosis.</p><p>Shares with Plectostoma palinhelix the spire and tuba form, but differs by having spire height between 2.3-2.6 mm.</p><p>Description.</p><p>Apex. Shape: moderately convex.</p><p>Spire. Height: 2.3-2.6 mm. Width: 1.5-1.7 mm. Number of whorls: 4 5/8-5. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: distinctly convex. Umbilicus: partially or completely closed by tuba.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible between right lateral and back view; the tuba coils upward until the first teleconch whorl of the spire. Tuba whorl length similar to the length of the last whorl of the spire. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similer to inner peristome, projected all around, except the posterior part, where two lateral sides are slightly more projected than the anterior side.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 7-9 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Bukit Chintamanis, Pahang (3°26'45"N, 102°0'51"E).</p><p>Distribution range. Endemic to the type locality (Figure 18C).</p><p>Conservation status.</p><p>Critically Endangered (B2ab(iii)+C2a(i) ver. 10.1). This species is endemic to a single limestone hill–Bukit Chintamanis. Most of the western part of this hill is gone due to the quarry activity in the past and this part is now covered by secondary vegetation. The rest of the outcrop is surrounded by plantation, which is subjected to periodic clearing and replanting. According to Berry (1961), live individuals can only be found at the rock surface (Site A in Berry 1961). Berry (1962) reports finding several thousand individuals at Site A.</p><p>A recent intensive survey for Plectostoma retrovertens was done at the type locality in August 2010 and May 2011. Site A is a rock surface smaller than 20 m2. It appears that the vegetation cover and habitat structure of Site A has not changed as compared to the assessment done by Berry (1962, 1964). However, only three live individuals were found during the survey in Aug. 2010. Furthermore, the surrounding of Bukit Chintamanis has been cleared in 2011. Judging by the population trends and habitat conditions together, this species is at the brink of extinction. The status of this species in a previous assessment (IUCN redlist) was: vulnerable D2 ver. 3.1 (Clements 2009c).</p><p>Discussion.</p><p>Plectostoma retrovertens and Plectostoma palinhelix are very distinct from other Plectostoma by having a very long tuba in relation to their spire. In fact, a preliminary phylogenetic analysis suggests that these two are basal species for all Peninsular Malaysia’s Plectostoma . These two species are located more 40 km apart on outcrops that belong to the same limestone facies (Figure 18C). The two species are very similar in their shell shape, but Plectostoma retrovertens is about one-third larger than Plectostoma palinhelix . Furthermore, the genetic divergence between the two species is 10%.</p></div>	https://treatment.plazi.org/id/A2D51D045BA52515849E8C1BE65CD31D	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
1EF0F7EEC8BBC5F068DE5443D1918DEB.text	1EF0F7EEC8BBC5F068DE5443D1918DEB.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma ikanensis	<div><p>Plectostoma ikanensis sp. n. Figures 17J, K, 34, 35, Appendix 11, 14</p><p>Type material.</p><p>Holotype: BOR 5645(1)</p><p>Paratypes: BOR 5507(6), BOR 5622(&gt;50), BOR 5504(&gt;10), V 9446(&gt;100), V 9320(6).</p><p>Etymology.</p><p>This species is named after its type locality–Gua Ikan.</p><p>Diagnosis.</p><p>Shares with Plectostoma kayiani the general shell form, in terms of spire and tuba shape, but differs by having both thick and thin spiral lines.</p><p>Description for shell form 5504</p><p>(Figs 17K and 34, and Appendix 14). Apex. Shape: moderately convex.</p><p>Spire. Height: 1.7 mm. Width: 1.3 mm. Number of whorls: 4 1/8-4 1/4. Apical spire shape: depressed conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: none. Basal teeth: none</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca.3/4-7/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where left lateral sides are slightly more projected than the anterior and right lateral side.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 5 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Description for shell form 5507</p><p>(Figs 17J and 35, and Appendix 11). Apex. Shape: moderately convex.</p><p>Spire. Height: 1.8-1.9 mm. Width: 1.3 mm. Number of whorls: 3 7/8-4. Apical spire shape: depressed conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in left lateral view. Tuba whorl length in proportion to spire last whorl: ca. 5/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Aperture with double peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where left lateral sides are slightly more projected than the anterior and right lateral side.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 7 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Gua Ikan in the State of Kelantan (5°21'9"N, 102°1'34"E).</p><p>Distribution range. In addition to the type location, this species also occurs at nearby limestone hills as far as 30 km away (Figure 18C).</p><p>Conservation status.</p><p>Least concern. Living populations of Plectostoma ikanensis were recorded at the type locality in 2011. The type locality is gazetted as recreation forest.</p><p>Discussion.</p><p>The two forms of Plectostoma ikanensis were found in the type locality at two different parts of the hill that within a distance of 100 m. The overall shell appearances of these two forms are very different, especially in terms of tuba coiling direction and spire shape. Interestingly, one of the Plectostoma ikanensis forms (i.e. BOR 5507) is very similar to Plectostoma davisoni on the basis of these two shell characters. In most of the other Plectostoma species examined in this study, tuba coiling direction and spire shape are rather stable characters within a species. Nevertheless, both Plectostoma ikanensis forms lack a constriction which unite them and distinguish them from other similar species (see Diagnosis). In addition to the morphological evidence, we found that the genetic divergence of these two forms is smaller than 1% (Table 4), and our preliminary phylogenetic analysis shows that the two forms are reciprocally monophyletic. We therefore conclude that they be classified as the same species.</p></div>	https://treatment.plazi.org/id/1EF0F7EEC8BBC5F068DE5443D1918DEB	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
400AB12CDF5ED813B0593611F9AB23A0.text	400AB12CDF5ED813B0593611F9AB23A0.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma kayiani	<div><p>Plectostoma kayiani sp. n. Figure 36, Appendix 11</p><p>Type material.</p><p>Holotype: RMNH 330803 (1). Paratypes: V 8883(6), V 14243(1).</p><p>Etymology .</p><p>This species is named after Kay Arnold and Ian Mellsop from New Zealand, who have generously supported wildlife conservation work in many parts of Peninsular Malaysia, including the forests around Lake Kenyir where this species was discovered.</p><p>Diagnosis.</p><p>Shares with Plectostoma ikanensis the general shell form, in terms of spire and tuba shape, but differs by lacking thick spiral lines.</p><p>Description.</p><p>Apex. Shape: slightly to moderately convex.</p><p>Spire. Height: 1.4-1.6 mm. Width: 1.2-1.4 mm. Number of whorls: 3 1/2-3 3/4. Apical spire shape: depressed conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible from front view. Tuba whorl length in proportion to spire last whorl: ca. 5/8-3/4. Proportion of tuba that attaches to spire: almost whole except the part near the aperture.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similer to inner peristome, projected all around, except the posterior part, where left lateral sides are slightly more projected than the anterior and right lateral side.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 8-10 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Gua Bewah, Tasik Kenyir (4°51'3"N, 102°43'21"E).</p><p>Distribution range. To date, this species is only known to occur at two neighbouring limestone outcrops, namely, Gua Bewah and Gua Taat at the southern part of Tasik Kenyir (Figure 18C).</p><p>Conservation status.</p><p>Least concern. The outcrops where this species is found, are partially submerged in Southeast-Asia’s largest man-made lake, Tasik Kenyir. Despite this, there is a good forest cover around and on the limestone outcrops. Furthermore, these two hills are located in a protected National Park.</p><p>Discussion.</p><p>This species occurs sympatrically with Plectostoma tohchinyawi and Plectostoma whitteni .</p></div>	https://treatment.plazi.org/id/400AB12CDF5ED813B0593611F9AB23A0	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
4C8EF3AE676164E4CF054CF1CA790340.text	4C8EF3AE676164E4CF054CF1CA790340.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma davisoni	<div><p>Plectostoma davisoni sp. n. Figure 37, Appendix 9, 10</p><p>Type material.</p><p>Holotype: BOR 5646(1)</p><p>Paratypes: ZMA 162069(&gt;25), ZMA 162070(3), ZMA 162071(&gt;50), ZMA 162146(7), ZMA 162147(8), BOR 5508(&gt;25), BOR 5626(&gt;25), BOR 5641(9), V 8652(6), V 8929(&gt;25), V 9206(6), V 8265(&gt;10), V 8301(&gt;25), V 9243(&gt;50), V 9340(7), V 9417(7), V 14242(5).</p><p>Diagnosis.</p><p>Shares with Plectostoma relauensis the general shell form, in terms of apex, spire, and tuba shape, but differs by having two parietal constriction teeth.</p><p>Etymology.</p><p>This species is named after Dr. Geoffrey Davison, who has been involved in the conservation of limestone hills in Malaysia, and has collected a lot of snail specimens, many of which are included in this revision of Plectostoma from Malaysia.</p><p>Description.</p><p>Apex. Shape: slightly to moderately convex.</p><p>Spire. Height: 1.6-2.0 mm. Width: 1.4-1.5 mm. Number of whorls: 3 5/8-4 7/8. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately to distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in frontal view. Tuba whorl length in proportion to spire last whorl: ca. 5/8-3/4. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similer to inner peristome, projected all around, except the posterior part, where the two lateral sides are slightly more projected than the anterior side.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 6-7 ribs per mm. Rib intensity: thin. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Limestone hill on the right hand side of the road D29, at km 17 when travelling from Jelawang to Gua Musang (4°59'4"N, 101°57'53"E).</p><p>Distribution range. This species has a very large distribution range, ca. 80 km diameter. It can be found in many limestone outcrops in the central part of Peninsular Malaysia, mainly in the State of Kelantan (Figure 17D). In addition, it can also be found in a cluster of limestone hills located at upper Sungai Keniyam Kecil in Taman Negara (ca. 60 km from Gua Musang).</p><p>Conservation status.</p><p>Least concern. This is a widespread species. Although many hills in Kelantan are being degraded and surrounded by oil palm plantations, there are a few well protected hills in Taman Negara in Pahang, where this species occurs.</p><p>Discussion.</p><p>This species is highly variable in the shell form (Appendix 9 and Appendix 10), and has a very wide distribution range which partly overlaps with many other Plectostoma species (Figure 18). It is very densely distributed in the State of Kelantan, parapatric with Plectostoma christae . The species becomes more sparse toward the limestone hills in Taman Negara, Pahang (Figure 18C). In view of this, it is possible that the species actually consists of two or more cryptic species, and thus more genetic data are needed.</p></div>	https://treatment.plazi.org/id/4C8EF3AE676164E4CF054CF1CA790340	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
C8A6DEFAAB5E068C80066A0FAED95156.text	C8A6DEFAAB5E068C80066A0FAED95156.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma relauensis	<div><p>Plectostoma relauensis sp. n. Figures 17P, 38, Appendix 13</p><p>Type material.</p><p>Holotype: BOR 5647(1). Paratypes: BOR 463(2), BOR 5511(&gt;25), V 8169(9).</p><p>Etymology.</p><p>This species is named after its type locality–Relau substation of Taman Negara, where Gua Gajah is located.</p><p>Diagnosis.</p><p>Shares with Plectostoma davisoni the general shell form, in terms of apex, spire, and tuba shape, but differs by having a single parietal constriction tooth.</p><p>Description.</p><p>Apex. Shape: slightly to moderately convex.</p><p>Spire . Height: 1.5-1.9 mm. Width: 1.5-1.6 mm. Number of whorls: 3 3/8-3 5/8. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately to distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: one. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in frontal view. Tuba whorl length in proportion to spire last whorl: ca. 1/2-5/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 4-7 ribs per mm. Rib intensity: thin. Shape: straight to slightly curved. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Gua Gajah in the Relau substation, Taman Negara. (4°38'15"N, 102°3'50"E).</p><p>Distribution range. This species also occurs at a limestone hill located about 20 km north of the type locality. BOR 463 was collection in Pulau Singa Besar, which is located about 300 km from type locality. The reliability of the collection data is dubious (see also BOR 462 of Plectostoma sinyumensis).</p><p>Conservation status.</p><p>Least Concern. A large living population of Plectostoma relauensis was found at Gua Gajah, which is located in the National Park.</p><p>Discussion.</p><p>This species occurs sympatrically with Plectostoma siphonostomum on the same limestone hills. Despite the high density of limestone hills in the area, where many other Plectostoma species occur, Plectostoma relauensis is only found in two of these (Figure 18).</p></div>	https://treatment.plazi.org/id/C8A6DEFAAB5E068C80066A0FAED95156	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
8910F3363E1388A8409942319C14B6C6.text	8910F3363E1388A8409942319C14B6C6.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma kakiense (Tomlin 1948) Tomlin 1948	<div><p>Plectostoma kakiense (Tomlin, 1948) Figures 17D, 39, Appendix 11</p><p>Opisthostoma kakiense Tomlin, 1948: 225, Plate 2 - figure 5 (original description).</p><p>Opisthostoma kakiense Tomlin, van Benthem Jutting (1952: 39).</p><p>Opisthostoma kakiense Tomlin, Ali and Yaakob (2001: 145).</p><p>Opisthostoma sp., Razalli et al. (2010: figure 2C).</p><p>Type material.</p><p>Holotype: BMNH 1948.10.2.3(1) (seen).</p><p>Other examined materials.</p><p>ZMA 136009(1), ZMA 162094(5), BOR 445(1), BOR 5516(&gt;25), BOR 5517(&gt;10), BOR 5598(3), V 8789(2).</p><p>Diagnosis.</p><p>Shares with Plectostoma kubuensis the general shell form, in terms of apex, spire, and tuba shape, but differs by having two parietal constriction teeth.</p><p>Description.</p><p>Apex. Shape: slightly to moderately convex.</p><p>Spire. Height: 1.7-2.1 mm. Width: 1.5-1.6 mm. Number of whorls: 3 3/4-4 1/4. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately to distinctly convex. Umbilicus: partially closed by tuba.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 5/8-3/4. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the two lateral sides are slightly more projected than the anterior side.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 8-10 ribs per mm. Rib intensity: thin. Shape: straight to slightly curved. Inclination: moderately prosoclin.</p><p>Distribution.</p><p>Type locality. Kaki Bukit (6°38'42"N, 100°12'6"E) (Figure 18C). Distribution range. Wang Kelian limestone outcrops.</p><p>Conservation status.</p><p>Near threatened. To date, only two populations are known for two large limestone outcrops in the vast limestone formation in Perlis. These two locations are Kaki Bukit and Wang Kelian, both located in the protected Wang Kelian State Park.</p><p>Although Kaki Bukit is a large limestone outcrop with good forest cover, the population density of Plectostoma kakiense is very low. During a survey in May 2011, this species was only found near the top of Kaki Bukit where several hundred individuals were found at one location (limestone wall) within an area of ca. 10 m2. There were several small populations (fewer than 10 individuals) in small pockets of suitable habitat. The population in Wang Kelian was recorded by Ali and Yaakob (2001), but its status is not known. No live or dead individuals were collected at the dozen isolated limestone hills located within 5 km around Wang Kelian State Park.</p><p>Discussion.</p><p>See discussion under Plectostoma kubuensis .</p></div>	https://treatment.plazi.org/id/8910F3363E1388A8409942319C14B6C6	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
A4B5696BA6140E8A6C51AFF0EF05516A.text	A4B5696BA6140E8A6C51AFF0EF05516A.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma kubuensis	<div><p>Plectostoma kubuensis sp. n. Figures 17F, 40, Appendix 12</p><p>Type material.</p><p>Holotype: BOR 5648(1). Paratypes: BOR 5518(&gt;25), BOR 5519(&gt;10).</p><p>Diagnosis.</p><p>Shares with Plectostoma kakiense the general shell form, in terms of apex, spire, and tuba shape, but differs by lacking constriction teeth.</p><p>Etymology.</p><p>This species is named after its type locality–Bukit Kubu, Perlis.</p><p>Description.</p><p>Apex. Shape: slightly to moderately convex.</p><p>Spire. Height: 1.6-2.0 mm. Width: 1.3-1.5 mm. Number of whorls: 3 5/8-4 1/4. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately to distinctly convex. Umbilicus: open or partially closed by tuba.</p><p>Constriction. Parietal teeth: none. Basal teeth: none.</p><p>Tuba. Coiling direction: type 3 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 5/8-3/4. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the left lateral sides are slightly more projected than the anterior and right lateral side.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 10-11 ribs per mm. Rib intensity: thin. Shape: straight to slightly curved. Inclination: moderately prosoclin.</p><p>Distribution.</p><p>Type locality. Bukit Kubu (6°24'15"N, 100°8'37"E) (Figure 18C).</p><p>Distribution range. Endemic to the type locality.</p><p>Conservation status.</p><p>Endangered (B2ab(iii)+C2a(i) ver. 10.1). During a survey of a dozen isolated limestone hills of the State of Perlis in May 2011, only Bukit Kubu was found to support a living population of Plectostoma kubuensis, consisting of several hundred individuals at the top of Bukit Kubu. Several very small populations (&lt;50 individuals) live at the other part of Bukit Kubu where the habitat is relatively more exposed and dry. Bukit Kubu is gazetted by Perlis State government as a recreation forest, and its surroundings consist of urban development and paddy fields.</p><p>Discussion.</p><p>From the conchological point of view, the overall shape and size of Plectostoma kubuensis and Plectostoma kakiense is almost the same. Nevertheless, two inconspicuous but significant shell characters, namely, basal and parietal constriction teeth, mark the difference between these two species. Despite the similarity in shell form, there is a great genetic distance between the two species (16%). The species occur at two limestone hills that lie about 30 km apart. During our survey, we could not find either species at the six limestone hills that are located between these two hills. A single Plectostoma shell was recorded by Norhanis et al. (2010) from Pulau Dayang Bunting, Langkawi, and might belong to this species.</p></div>	https://treatment.plazi.org/id/A4B5696BA6140E8A6C51AFF0EF05516A	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
7617F6268D09074C814E14CA0024E587.text	7617F6268D09074C814E14CA0024E587.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma laemodes (van Benthem Jutting 1961) van Benthem Jutting 1961	<div><p>Plectostoma laemodes (van Benthem Jutting, 1961) Figure 41, Appendix 12</p><p>Opisthostoma laemodes van Benthem Jutting, 1961: 40, plate 11 - figure 6 (original description).</p><p>Type material.</p><p>Holotype: ZMA 136010(1) (Seen). Paratypes: ZMA 136011(3) (Seen), ZMA 136012(3) (Seen), ZMA 136013(4) (Seen).</p><p>Other examined materials.</p><p>RMNH 156267(7), V 8490(&gt;25).</p><p>Diagnosis.</p><p>Shares with Plectostoma salpidomon the general shell form, in terms of apex, spire, and tuba shape, but differs by having the whole tuba attached to the spire.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 2.3-2.7 mm. Width: 1.6-1.8 mm. Number of whorls: 3 1/8-4 5/8. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately to distinctly convex. Umbilicus: open or partially closed by tuba.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 3 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 1/2-5/8. Proportion of tuba that attaches to spire: whole.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the left lateral sides are slightly more projected than the anterior and right lateral side.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 6-7 ribs per mm. Rib intensity: thin. Shape: straight to slightly curved. Inclination: prosoclin.</p><p>Distribution.</p><p>Type locality. Batu Tai Gadjah, Ulu Keniyam Kechil, Taman Negara, Pahang Malaysia (4°37'0"N, 102°25'14"E) (Figure 18B).</p><p>Distribution range. This species mainly occurs in a cluster of limestone hills that are located at upper Sungai Keniyam Kecil in Taman Negara (Figure 18B). In addition, this species has been recorded from Bukit Jereng, Blau, Kelantan, which is about 80 km west from Sungai Keniyam Kecil.</p><p>Conservation status.</p><p>Least concern. Although no living population has been recorded so far, several large and well protected limestone hills in the Taman Negara probably support a viable population.</p><p>Discussion.</p><p>From a conchological point of view, this species is similar to Plectostoma salpidomon; the two may be closely related. In view of biogeography, this species occurs parapatrically with Plectostoma salpidomon, which occurs in the limestone hills in between Bukit Jereng and the limestone cluster at Sungai Keniyam Kecil (Figure 18B). Further genetic data are needed to verify the taxonomic status of Plectostoma laemodes .</p></div>	https://treatment.plazi.org/id/7617F6268D09074C814E14CA0024E587	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
ADF2F3DA40F4851BC813CF3800E87A4A.text	ADF2F3DA40F4851BC813CF3800E87A4A.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma salpidomon (van Benthem Jutting 1952) van Benthem Jutting 1952	<div><p>Plectostoma salpidomon (van Benthem Jutting, 1952) Figures 17A, 42, Appendix 13</p><p>Opisthostoma salpidomon van Benthem Jutting, 1952: 42, figure 21 (original description).</p><p>Opisthostoma salpidomon van Benthem Jutting, van Benthem Jutting (1961: 39).</p><p>Type material.</p><p>Holotype: ZMA 136045(1) (Seen). Paratypes: ZMA 136046(&gt;25) (Seen), ZMA 136047(2) (Seen), ZMA 136048(&gt;10) (Seen).</p><p>Other examined materials.</p><p>ZMA 162137(&gt;25), BOR 459(1), BOR 5539(&gt;10), BOR 5540(&gt;10), BOR 5541(5), BOR 5542(&gt;25), BOR 5569(&gt;25), BOR 5611(1), V 8171(4), V 8658(&gt;25), V 8706(6), V 9116(7), V 9292(3).</p><p>Diagnosis.</p><p>Shares with Plectostoma laemodes the general shell form, in terms of apex, spire, and tuba shape, but differs by having a tuba that attaches partly to the spire.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 2.5-2.8 mm. Width: 1.5-1.7 mm. Number of whorls: 4 5/8-5 1/4. Apical spire shape: depressed conical. Basal spire shape: ovoid. Whorl periphery: moderately to distinctly convex. Umbilicus: completely or partially closed by tuba.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 3/4-7/8. Proportion of tuba that attaches to spire: less than 2/3.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the two lateral sides are slightly more projected than the anterior side.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 5-6 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: prosoclin.</p><p>Distribution.</p><p>Type locality. Gua Bama, Pahang (4°11'37"N, 101°58'2"E) (Figure 18B).</p><p>Distribution range. Plectostoma salpidomon can be found in many limestone hills in the valley in between the Titiwangsa, Tahan and Benom mountain ranges (Figure 18B).</p><p>Conservation status.</p><p>Least concern. Plectostoma salpidomon has a wide distribution range. Living populations have been recorded in many limestone hills and some of these are in protected areas.</p><p>Discussion.</p><p>See discussion under Plectostoma laemodes .</p></div>	https://treatment.plazi.org/id/ADF2F3DA40F4851BC813CF3800E87A4A	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
10D549CCDA9ACB520D567D3E19AEB32E.text	10D549CCDA9ACB520D567D3E19AEB32E.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma kitteli (Maassen 2002) Maassen 2002	<div><p>Plectostoma kitteli (Maassen, 2002) Figure 43, Appendix 11</p><p>Opisthostoma kitteli Maassen, 2002: 176, figures 35 &amp; 36 (original description).</p><p>Type material.</p><p>Holotype: RMNH 92942(1) (seen). Paratypes: RMNH 92956(&gt;25) (Seen), V 12697(9) (Seen).</p><p>Other examined materials.</p><p>BOR 1697(&gt;10). YSC.</p><p>Diagnosis.</p><p>Shares with Plectostoma charasense, Plectostoma tohchinyawi, and Plectostoma klongsangensis the general shell form, in terms of apex, spire, and tuba shape, but differs by lacking thick spiral lines and basal constriction teeth.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 2.9-3.0 mm. Width: 1.7-1.8 mm. Number of whorls: 5 5/8-5 3/4. Apical spire shape: oblong conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: partially closed by tuba.</p><p>Constriction . Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 3/4-7/8. Proportion of tuba that attaches to spire: less than 2/3.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the two lateral sides are slightly more projected than the anterior side.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 5-6 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. Cave Pangian (local name Ngalau Pangian - 0°27'45"S, 100°45'8"E)</p><p>Distribution range. This species was also found at a limestone hill near Kampung Desa Gadut, West Sumatra (0°15'36"S, 100°44'16"E). This hill is located about 20 km from the type locality. In addition, a private collector (Yansen Chen, pers. comm.) also collected the same species at Tiangko cave, about 230 km from the type locality (Figure 18B). It therefore appears to have a wide distribution range in Sumatra. It may thus be expected that the limestone outcrops around the three hills mentioned, might support the same species.</p><p>Conservation status.</p><p>Data deficient. This species has only been recorded from three limestone hills in West Sumatra. The population status and actual distribution range of this species remain unknown. Nevertheless, concern is warrented, as the surroundings of the type locality and several other limestone outcrops in the same area are highly degraded.</p><p>Discussion.</p><p>There are large areas in the Northern and Western provinces of Sumatra that are covered by limestone hills (Verstappen and Genootschap 1973). Despite intensive malacological surveys in some of these areas (van Benthem Jutting 1959), no Plectostoma species was found until 1997. To date, Plectostoma kitteli is the only Plectostoma species found in Sumatra (Maassen 2002).</p></div>	https://treatment.plazi.org/id/10D549CCDA9ACB520D567D3E19AEB32E	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
4BB25E27D19BFB248CDBF88981D72A0B.text	4BB25E27D19BFB248CDBF88981D72A0B.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma klongsangensis (Panha 1997) Panha 1997	<div><p>Plectostoma klongsangensis (Panha, 1997)</p><p>Opisthostoma klongsangensis Panha, 1997: 133, figure 1 (original description).</p><p>Opisthostoma klongsangensis Panha, Hemmen and Hemmen (2001: 39).</p><p>Opisthostoma klongsangensis Panha, Nabhitabhata (2009: 50).</p><p>Type material.</p><p>Holotype: CUIZMD 0001 (not seen). Paratypes: CUIZMDM 0002 (Not seen), CUIZMDM 0003 in ZMA (Not seen, specimen could not be located in ZMA).</p><p>Diagnosis.</p><p>Shares with Plectostoma charasense, Plectostoma tohchinyawi, and Plectostoma kitteli the general shell form, in terms of apex, spire, and tuba, but differs by having both thin and thick spiral lines, and the left lateral side of outer peristome projected more than three times the distance of the right lateral side of outer peristome.</p><p>Description (estimated from figure in Panha 1996). Apex. Shape: distinctly convex.</p><p>Spire. Height: 2.3 mm. Width: 1.7 mm. Number of whorls: 5 1/2. Apical spire shape: oblong conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: open.</p><p>Constriction. Unknown.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 7/8. Proportion of tuba that attaches to spire: less than 2/3.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: different from inner peristome, the left lateral side of outer peristome is projected from inner peristome about 0.7 mm, and the right side of outer peristome about 0.1 mm, but narrowed toward the anterior part of outer peristome.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 3 ribs per mm. Rib intensity: thick. Shape: single-looped. Inclination: prosoclin.</p><p>Distribution.</p><p>Type locality. Khlong Saeng Wildlife Sanctuary Surat Thani Province, Thailand (8°31'13"N, 98°25'17"E) (Figure 18B).</p><p>Distribution range. Unknown.</p><p>Conservation status.</p><p>Data deficient. This species has been collected once in Khlong Saeng Wildlife Sanctuary.</p><p>Discussion .</p><p>From a conchological point of view, this species appears not to be related to Plectostoma species from the Malay Peninsula and Sumatra. Instead, it is almost identical to Plectostoma mirabile, an endemic species from Gomantong Cave, Sabah, Borneo. These two species are separated by the South China Sea and located more than 2000 km apart. It remains to be determined whether this similarity is due to a disjunct distribution of closely related forms, or rather convergent shell evolution.</p><p>The taxonomic status of the species remains doubtful. In the original publication, Panha (1996) compared it with Plectostoma heteropleuron (Vermeulen 1994) and Plectostoma perspectivum (Vermeulen, 1994) from Northern Borneo, but not with Plectostoma mirabile (Smith, 1893), which has an almost identical shell as Plectostoma klongsangensis . This is all the more remarkable, as Plectostoma mirabile (Smith, 1893) was treated in Vermeulen (1994), where both Plectostoma heteropleuron and Plectostoma perspectivum were originally described.</p><p>In conclusion, more data are needed to verify the taxonomic status and the interesting biogeography of this species.</p></div>	https://treatment.plazi.org/id/4BB25E27D19BFB248CDBF88981D72A0B	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
C99409CC25800F89FBED73CB64C0F312.text	C99409CC25800F89FBED73CB64C0F312.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma charasense (Tomlin 1948) Tomlin 1948	<div><p>Plectostoma charasense (Tomlin, 1948) Figure 44, Appendix 14</p><p>Opisthostoma charasense Tomlin, 1948: 225, Plate 2 - figure 4 (original description).</p><p>Opisthostoma charasense Tomlin, van Benthem Jutting (1952: 42).</p><p>Type material.</p><p>Holotype: BNHM 1948.10.2.2(1) (Seen).</p><p>Other examined materials.</p><p>ZMA 162063(&gt;10), ZMA 162064(&gt;10).</p><p>Diagnosis.</p><p>Shares with Plectostoma kitteli, Plectostoma tohchinyawi, and Plectostoma klongsangensis the general shell form, in terms of apex, spire, and tuba shape, but differs by lacking thick spiral lines and by having two basal constriction teeth.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 1.9-2.0 mm. Width: 1.3-1.4 mm. Number of whorls: 4 1/8. Apical spire shape: oblong conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: two. Basal teeth: two.</p><p>Tuba. Coiling direction: type 2 and aperture visible from right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 7/8. Proportion of tuba that attaches to spire: less than 1/2.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 4 ribs per mm. Rib intensity: thick. Shape: slightly curved to single-humped. Inclination: moderately prosoclin.</p><p>Distribution.</p><p>Type locality. Gua Charas, limestone hill near Sungai Lembing in the state of Pahang, Malaysia (3°54'27"N, 103°8'47"E).</p><p>Distribution range. Until now, this species has been recorded from two neighbouring limestone hills, namely, Gua Charas and Bukit Panching. However, the whole hill of Bukit Panching has been lost to quarrying (Figure 18B).</p><p>Conservation status.</p><p>Critically Endangered (B2ab(iii)+C2a(i) ver. 10.1). Gua Charas might support a viable population. However, the hill is currently surrounded by oil palm plantation with a very narrow forested buffer zone. No living individuals or fresh dead shells were found at Gua Charas after exhaustive search during several sampling trips in 2010 and 2011.</p><p>Discussion.</p><p>The taxonomic status of this species is stable. Although the two neighbouring species, Plectostoma tohchinyawi and Plectostoma praeco, are similar to Plectostoma charasense, there are a few key shell characters that separate Plectostoma charasense from the others. See discussion under Plectostoma tohchinyawi for more discussion about the biogeography of this species.</p></div>	https://treatment.plazi.org/id/C99409CC25800F89FBED73CB64C0F312	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
72C381F636EBBF533D28E77AFFEC077C.text	72C381F636EBBF533D28E77AFFEC077C.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma tohchinyawi	<div><p>Plectostoma tohchinyawi sp. n. Figure 17S, 45, Appendix 14</p><p>Type material.</p><p>Holotype: BOR 5649(1). Paratypes: BOR 5533(&gt;10), BOR 5534(&gt;10), BOR 5535(&gt;10), V 8811(&gt;25).</p><p>Diagnosis.</p><p>Shares with Plectostoma charasense , Plectostoma kitteli, and Plectostoma klongsangensis the general shell form, in terms of apex, spire, and tuba shape, but differs by having both thin and thick spiral lines, and the left lateral side of outer peristome projected not more than twice the width of the right lateral side of outer peristome.</p><p>Etymology.</p><p>This species is named after Dato’ Toh Chin Yaw, who was the Chairman of Industry, Trade and Environment Committee in the Terengganu State Government between 2008 and 2013. It is rare to find politicians working closely with the public for wildlife conservation. During his time in office, Dato’ Toh was tireless in his efforts to promote and preserve Terengganu’s natural heritage. One of his most influential decisions was getting the State to ban the hunting of threatened flying foxes ( Pteropus vampyrus). Before he left office, he was working with scientists to gazette the Kenyir Wildlife Corridor as a protected area and was helping to secure funds to improve anti-poaching efforts in that area.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 2.1-2.4 mm. Width: 1.3-1.5 mm. Number of whorls: 4 7/8-5 3/8. Apical spire shape: oblong conical. Basal spire shape: conical. Whorl periphery: distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 7/8-8/8. Proportion of tuba that attaches to spire: less than 1/2.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the two lateral sides are distinctly more projected than the anterior side.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 4-6 ribs per mm. Rib intensity: thick. Shape: slightly curved to single-humped. Inclination: prosoclin.</p><p>Distribution.</p><p>Type locality. Gua Bewah, Tasik Kenyir (4°51'3"N, 102°43'21"E).</p><p>Distribution range. To date, this species is only known to occur at two neighbouring limestone outcrops, namely, Gua Bewah and Gua Taat at the Southern part of Tasik Kenyir (Figure 18B).</p><p>Conservation status.</p><p>Least concern. The only two limestone outcrops where this species was found are partially submerged in Southeast Asia’s largest man-made lake, Tasik Kenyir. Nonetheless, there is good forest cover around and on the limestone outcrops. Furthermore, these two hills are located in the Taman Negara Pahang, which is a prioritised protected area.</p><p>Discussion.</p><p>From a conchological point of view, this species is related to Plectostoma charasense . Both are thought to be affiliated with the Plectostoma species from North Borneo. Plectostoma tohchinyawi has a high conical spire, thick and projected radial ribs, and a long detached tuba. These are the typical characteristics for dozens of Plectostoma species in North Borneo. In addition, Plectostoma tohchinyawi and Plectostoma charasense live on the five lenticular limestone outcrops that are the easternmost outcrops of the Malay Peninsula, thus closest geographically to Borneo (Figure 18B).</p></div>	https://treatment.plazi.org/id/72C381F636EBBF533D28E77AFFEC077C	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
3C4AD7FA8E697208ECC45A923D55A2E5.text	3C4AD7FA8E697208ECC45A923D55A2E5.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma annandalei (Sykes 1903) Sykes 1903	<div><p>Plectostoma annandalei (Sykes, 1903)</p><p>Opisthostoma annandalei Sykes, 1903: 198, Plate 20 - figures 4 &amp; 5 (original description).</p><p>Opisthostoma annandalei Sykes, Laidlaw (1928: 36).</p><p>Opisthostoma annandalei Sykes, van Benthem Jutting (1952: 41).</p><p>Type material.</p><p>Not seen.</p><p>Diagnosis.</p><p>Shares with Plectostoma laidlawi, Plectostoma tenggekensis, and Plectostoma praeco the general shell form, in terms of spire and tuba shape, but differs by having slightly convex whorl periphery and straight ribs.</p><p>Description</p><p>(estimated from figure in Sykes 1903). Apex. Shape: moderately convex.</p><p>Spire. Height: 2 mm. Width: 1.3 mm. Number of whorls: 4 1/2. Apical spire shape: depressed conical. Basal spire shape: conical. Whorl periphery: moderately convex. Umbilicus: Open.</p><p>Constriction. Unknown.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: approximately the same as the spire’s last whorl length. Proportion of tuba that attaches to spire: less than 1/2.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: same as inner peristome and uniformly projected all around, except the posterior part.</p><p>Spiral lines. Unknown</p><p>Radial ribs. Rib density: 5 ribs per mm. Rib intensity: unknown. Shape: straight. Inclination: orthoclin.</p><p>Distribution.</p><p>Type locality. This species is only known from its type locality, Jalor (Biserat). The exact location was not described in the original publication of this species. From the collectors’ report (Annandale and Robinson 1913), we estimated the location and name of the limestone hill from a map in the report. This hill was named Bukit Bayu. Later, we estimated its coordinates from Google Earth (6°16'48"N, 101°13'35"E) (Figure 18B).</p><p>Distribution range. Unknown.</p><p>Conservation status.</p><p>Data Deficient.</p><p>Discussion.</p><p>This species has not been seen or collected after the original description. The type specimens cannot be located. Sykes (1903) mentioned that it is similar to Plectostoma laidlawi but he did not explain explicitly in what way. This is not unexpected, as Plectostoma laidlawi was the only one Plectostoma known from Peninsular Malaysia at the time, although more than 20 Plectostoma species had already been described from Borneo. Thus, one can assume that the statement made by Sykes was based on the geographical proximity.</p><p>Interestingly, Plectostoma panhai was described from a limestone hill located just 8 km from the location where Plectostoma annandalei was found. In addition to the geographical proximity, the two neighbouring species are similar in several shell characteristics. The shell spires are very similar in terms of number of whorls, overall shape and size. On the other hand, the main difference between these two species is the tuba coiling direction (type 1 vs. type 2).</p></div>	https://treatment.plazi.org/id/3C4AD7FA8E697208ECC45A923D55A2E5	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
23AC65294678C8838B54FC2249B7ED57.text	23AC65294678C8838B54FC2249B7ED57.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma praeco (van Benthem Jutting 1961) van Benthem Jutting 1961	<div><p>Plectostoma praeco (van Benthem Jutting, 1961) Figure 46, Appendix 14</p><p>Opisthostoma praeco van Benthem Jutting, 1961: 39, Plate 2 - figure 5 (original description).</p><p>Type material.</p><p>Holotype: ZMA 136034(1) (Seen). Paratypes: ZMA 136041(&gt;50) (Seen), ZMA 136042(&gt;25) (Seen).</p><p>Other examined materials.</p><p>ZMA 162150(&gt;100), ZMA 162151(&gt;100), ZMA 162152(&gt;100), ZMA 162153(&gt;10).</p><p>Diagnosis.</p><p>Shares with Plectostoma laidlawi, Plectostoma tenggekensis, and Plectostoma annandalei the general shell form, in terms of spire and tuba shape, but differs by having slightly curved ribs.</p><p>Description.</p><p>Apex. Shape: distinctly convex.</p><p>Spire. Height: 2.0-2.2 mm. Width: 1.8-2.0 mm. Number of whorls: 4 1/4-4 5/8. Apical spire shape: depressed conical. Basal spire shape: conical. Whorl periphery: moderately to distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 5/8-7/8. Proportion of tuba that attaches to spire: more than 1/3 but less than 1/2.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the left lateral sides are slightly more projected than the anterior and right lateral side.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 6-7 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: moderately prosoclin.</p><p>Distribution.</p><p>Type locality. Batu Che Derani, Taman Negara Pahang (4°35'57"N, 102°25'57"E).</p><p>Distribution range. Plectostoma praeco has been recorded from four other hills at upper Sungai Keniyam Kecil, which is in the vicinity of the type locality (Figure 18B).</p><p>Conservation status.</p><p>Least concern. All the limestone hills where Plectostoma praeco occurs, are located in the National Park.</p><p>Discussion.</p><p>There is no genetic information for Plectostoma praeco . Morphological similarity suggests that Plectostoma praeco and Plectostoma tenggekensis are closely related. Each of the two species has a narrow distribution range and they are separated from each other by at least 50 km.</p></div>	https://treatment.plazi.org/id/23AC65294678C8838B54FC2249B7ED57	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
4620E1022FD16A8171696DF7EFB9596E.text	4620E1022FD16A8171696DF7EFB9596E.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma tenggekensis	<div><p>Plectostoma tenggekensis sp. n. Figure 47, Appendix 14</p><p>Type material.</p><p>Holotype: BOR 5650(1). Paratypes: V 13554(5), BOR 444(4), BOR 5596(&gt;10).</p><p>Diagnosis.</p><p>Shares with Plectostoma laidlawi, Plectostoma annandalei, and Plectostoma praeco the general shell from, in terms of spire and tuba shape, but differs by having single-humped shaped ribs.</p><p>Etymology .</p><p>This species is named after its type locality–Bukit Tenggek, Kuantan, Pahang.</p><p>Description.</p><p>Apex. Shape: moderately convex.</p><p>Spire. Height: 1.6-1.7 mm. Width: 1.3-1.4 mm. Number of whorls: 4-4 1/4. Apical spire shape: depressed. Basal spire shape: conical. Whorl periphery: moderately convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 5/8 of the spire last whorl length. Proportion of tuba that attaches to spire: less than 1/3.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the left lateral sides are slightly more projected than the anterior and right lateral side.</p><p>Spiral lines. Thick lines: absent. Thin lines: present.</p><p>Radial ribs. Rib density: 6-7 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: moderately prosoclin.</p><p>Distribution.</p><p>Type locality. Bukit Tenggek, Pahang (4°0'51"N, 103°9'34"E).</p><p>Distribution range. Endemic to type locality (Figure 18B).</p><p>Conservation status.</p><p>Critically Endangered (B2ab(iii)+C2a(i) ver. 10.1). The entire Bukit Tenggek will be gone by 2014 because of quarrying activity.</p><p>Discussion.</p><p>See discussion under Plectostoma praeco .</p></div>	https://treatment.plazi.org/id/4620E1022FD16A8171696DF7EFB9596E	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
9978D1AD2EAC81C877637BA85B4BBEA9.text	9978D1AD2EAC81C877637BA85B4BBEA9.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Plectostoma laidlawi (Sykes 1902) Sykes 1902	<div><p>Plectostoma laidlawi (Sykes, 1902) Figures 17O, 48, 49, Appendix 15</p><p>Opisthostoma laidlawi Sykes, 1902a: 22 (original description).</p><p>Opisthostoma laidlawi Sykes, Sykes (1902b: Plate 3 - figures 13 &amp; 14).</p><p>Opisthostoma laidlawi Sykes, von Moellendorff (1902: 143).</p><p>Opisthostoma laidlawi Sykes, Laidlaw (1928: 36).</p><p>Opisthostoma laidlawi Sykes, van Benthem Jutting (1952: 41).</p><p>Opisthostoma laidlawi Sykes, Ito et al. (2009: 58).</p><p>Opisthostoma laidlawi Sykes, Sasaki (2010: 126, figure 2.7B).</p><p>Type material.</p><p>Holotype: Not Seen. Paratype: ZMA 136014(1) (Seen).</p><p>Other examined materials.</p><p>BMNH C_ACC1825(1), BOR 5510(&gt;25), BOR 5571(2), RMNH 156268(1), ZMA 162095(2), ZMA 162097(&gt;25), ZMA 162099(&gt;10), ZMA 162100(&gt;25), ZMA 162096(1), V5558(1), V 7878(3), V 8345(&gt;100), V 8476(&gt;25), V 8670(&gt;25), V 8693(&gt;50), V 8950(&gt;50), V 9044(&gt;25), V 9109(&gt;25), V 9125(&gt;25), V 9359(6).</p><p>Diagnosis.</p><p>Shares with Plectostoma annandalei, Plectostoma tenggekensis, and Plectostoma praeco the general shell form in terms of spire and tuba shape, but differs by having a distinctly convex whorl periphery and straight ribs.</p><p>Description.</p><p>Apex. Shape: moderately to distinctly convex.</p><p>Spire. Height: 1.6-2.3 mm. Width: 1.3-1.8 mm. Number of whorls: 3 5/8-4. Apical spire shape: depressed conical. Basal spire shape: conical to ovoid. Whorl periphery: distinctly convex. Umbilicus: open.</p><p>Constriction. Parietal teeth: two. Basal teeth: none.</p><p>Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 5/8-7/8. Proportion of tuba that attaches to spire: varies from completely attached to as much as half of the tuba detached from spire.</p><p>Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the two lateral sides are slightly more projected than the anterior side or left lateral sides slightly more projected than the anterior and right lateral side.</p><p>Spiral lines. Thick lines: present. Thin lines: present.</p><p>Radial ribs. Rib density: 5-6 ribs per mm. Rib intensity: thin. Shape: straight to slightly curved. Inclination: moderately prosoclin.</p><p>Distribution.</p><p>Type locality. "Kelantan, Malay Peninsula", collected by J. Waterstradt (Sykes 1902). According to Waterstradt’s (1902) itinerary, he visited one of the limestone hills at Kampung Pulai. The Pulai Princess cave (4°47'38"N, 101°56'31"E) fits perfectly with Waterstradt’s descriptions on the local population, temples and hill’s topography; he also described that he and his collectors sampled shells here (Waterstradt 1902: 9-10). We conclude that Pulai Princess Cave must be the type locality of Plectostoma laidlawi . However, a recent survey at the highly degraded Bukit Pulai Princess cave failed to retrieve any shells of Plectostoma .</p><p>Distribution range. This species occurs on the limestone hills along Berok River and Nenggiri River (Figure 18B).</p><p>Conservation status.</p><p>Vulnerable (D2 ver. 10.1). Living populations were present on only two limestone hills during a survey in May 2011. All the limestone hills for which this species is known are surrounded by degraded forest and oil palm plantation.</p><p>Discussion.</p><p>The morphology of this species is quite variable in shell size and degree of attachment of the tuba to the spire. The distribution range partially overlaps with that of Plectostoma davisoni . It is possible that the species actually consists of two or more cryptic species, and thus more genetic data are needed.</p></div>	https://treatment.plazi.org/id/9978D1AD2EAC81C877637BA85B4BBEA9	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Liew, Thor-Seng;Vermeulen, Jaap Jan;Marzuki, Mohammad Effendi bin;Schilthuizen, Menno	Liew, Thor-Seng, Vermeulen, Jaap Jan, Marzuki, Mohammad Effendi bin, Schilthuizen, Menno (2014): A cybertaxonomic revision of the micro-landsnail genus Plectostoma Adam (Mollusca, Caenogastropoda, Diplommatinidae), from Peninsular Malaysia, Sumatra and Indochina. ZooKeys 393: 1-107, DOI: http://dx.doi.org/10.3897/zookeys.393.6717, URL: http://dx.doi.org/10.3897/zookeys.393.6717
