taxonID	type	description	language	source
1B153E3AFF84FFBAF396CBF35E93FBA8.taxon	materials_examined	Material examined. Inside of Gesodokkuru Reef, off Arumonogui, Babelthuap I., Palau Is., ca. 20 m in depth, dredged, dead coral and sand; 1 ♂ (cb 4.5 × cl 4.4 mm), NSMT-Cr 30952; July 14, 1980; K. Baba leg.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF84FFBAF396CBF35E93FBA8.taxon	discussion	Remarks. This specimen is small, but agrees with the line drawings by De Man (1888: pl. 18 fig. 3), Alcock (1901: pl. 3 fig. 11), Campbell and Stephenson (1970: fig. 3 A) and Lewinsohn (1977: fig. 2 a), with the photographs by Takeda (1973: pl. 1 fig. A) and McLay (1993: fig. 18 d), and also with the taxonomic notes by Ihle (1913). Especially, the recent description and taxonomic discussion by McLay (1993) are elaborate. The most remarkable character of this species is the armature of the carapace margin; the anterolateral margin is armed with a large rightangled tooth rather close to the external orbital angle, which makes a distinct gap at the tooth, and the main anterolateral margin behind the tooth is almost straight, only weakly convergent, and followed by a blunt epibranchial tooth behind the shallow but distinct depression.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF84FFBAF396CBF35E93FBA8.taxon	distribution	Distribution. Widely distributed in the Indo-West Pacific from the Red Sea eastwards to the Marquesas Islands and northwards to the Philippines, 1 – 105 m in depth. Mclay (2001) recorded many specimens from the Marquesas Islands in the Polynesia, and Balss (1938) and Takeda (1973) recorded this species from the Gilbert and Palau Islands in the Micronesia, respectively.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF84FFB9F006CCD75AEAFD2A.taxon	materials_examined	Material examined. Off Kwannon, Koror I., Palau Is., dredged, with coralline algae; 1 juv. (cb 10.0 × cl 8.6 mm), NSMT-Cr 30953; June 17, 1980; K. Baba leg. ─ Kayangel Atoll., north of Babelthuap I., Palau Is., lagoon, dredged, 4 m in depth; 4 juv. (9.5 × 6.6 mm ─ 16.5 × 11.6 mm), NSMT-Cr 30954; July 6, 1980; K. Baba leg. Remarks. All of the five specimens examined are juvenile, but the carapace dorsal ornamentation and the shape of both chelipeds are close to those of the adult specimens, only with slightly narrower carapace contour. Buitendijk (1939: pl. 8 fig. 5) recorded and figured a young specimen of cb 8 mm as Calappa lophos (Herbst, 1782) dredged from 6 – 10 m in depth near Koepang, Timor, but the specimen should be referred to C. gallus instead, as the author herself considered its identification with some doubts. This species is commonly found at the tidal and subtidal sandy bottom. Galil (1997) recorded many specimens from various localities in the Indo-West Pacific. Distribution. Geographically known from the whole Indo-West Pacific, and bathymetrically from coral reefs and rocky shores down to 140 m. The records of C. gallus from the Atlantic were amended to those of C. galloides Stimpson, 1859, by Manning and Chace (1990). Takeda (1973) recorded this species from the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF87FFB9F3BCCB545BDFF9EA.taxon	materials_examined	Material examined. Inside of Gesodokkuru Reef, off Arumonogui, Babelthuap I., Palau Is., dredged, ca. 20 m in depth; 1 ovig. ♀ (cb 6.5 × cl 9.1 mm), NSMT-Cr 30955; July 13, 1980; K. Baba leg. Remarks. Stenorhynchus fissifrons Haswell, 1879, Achaeus tenuicollis Miers, 1886, and A. elongatus Sakai, 1938, were synonymized with A. curvirostris by Griffin and Tranter (1986). This long-neck species is characteristic in having the carapace with the tuberculate mesogastric and cardiac regions, the preorbital and supraorbital spines, and the sickle-shaped dactyli of the last two ambulatory legs. Distribution. Widely distributed in the Indo-West Pacific from Japan to Australia and New Zealand, and further to the western Indian Ocean, with bathymetric records from 3 to 165 m. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF87FFB9F3B3CEB65EBEFC5F.taxon	materials_examined	Material examined. Off Kwannon, Koror I., Palau Is., dredged; 1 ♀ (cb 8.6 × cl 12.0 mm), NSMT-Cr 30956; June 17, 1980; K. Baba leg.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF87FFB9F3B3CEB65EBEFC5F.taxon	discussion	Remarks. It is well known that the G 1 is the most important criterion for the definite identification of the Oncinopus species (Takeda and Miyake, 1969; Davie, 2011). The identification of females should be based mainly on the shape of the front, and the present female was identified as O. neptunus among the five congeneric species, because of the front divided into two lobes by a median small notch. Griffin and Tranter (1986) examined many specimens and fully discussed the taxonomic status of four species then known.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF87FFB9F3B3CEB65EBEFC5F.taxon	distribution	Distribution. Widely distributed in the whole Indo-West Pacific from Hawaii and Japan through some localities in the Philippines and Indonesia southwards to New Caledonia and the east coast of Australia, and to the east Africa and the Red Sea. The recorded bathymetric range is from 16 to 72 m. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF87FFBFF005CC215B9CFEE8.taxon	description	(Fig. 1 E) Material examined. Off Kwannon, Koror I., Palau Is., dredged; 1 ♀ (cb 10.5 × pcl 13.8 mm; rl 5.8 mm), NSMT-Cr 30957; June 17, 1980; K. Baba leg. Remarks. Griffin (1966) selected the lectotype specimen from the five specimens in the type series of Hyastenus sebae, with the photographs of the carapace in dorsal and ventral views, and later, Griffin (1976) showed that one specimen in the four paralectotypes of H. sebae belongs to H. convexus Miers, 1884, and the other three specimens belong to a new species, H. whitei. At present, as shown in Fig. 1 E, H. sebae is characteristic in having the strongly tuberculated carapace, with the short rostral spines, and readily distinguished from H. whitei in which the rostral spines are remarkably long, nearly as long as the pcl.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF87FFBFF005CC215B9CFEE8.taxon	distribution	Distribution. Japan (as H. cornigerus), many localities in the Philippines and Indonesian waters, Singapore, the Palau Islands, New Caledonia, and Western Australia. The bathymetric records are mostly in shallow waters from intertidal zone to at most ca. 50 m, but there are some unusual deep-water records from the Java Sea (538 m) and the Kai Islands (304 and 385 m) by Griffin and Tranter (1986).	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF81FFBFF396C9B258A6FB22.taxon	description	(Fig. 1 D) Material examined. Off Kwannon, Koror I., Palau Is., dredged; 1 ♂ (cb 17.0 mm excluding branchial spines × pcl 25.2 mm including posterior tubercle; rl 10.5 mm), NSMT-Cr 30958; June 17, 1980; K. Baba leg. Remarks. The records of this species are not so many, but there is no doubt for its identification as Naxioides hirta due to the good representations by the original author (A. Milne-Edwards, 1865) and some later authors such as Hilgendorf (1879, as Podopisa petersii), Sakai (1938), and Takeda et al. (2019). The pear-shaped carapace (Fig. 1 D) with many granules of various sizes and a sharp epibranchial spine at each side suggests some Hyastenus species, but the anterior part of the carapace is fairly strongly deflexed and each rostral spine is armed with a subsidiary spine at its dorsal median surface, which is not a character diagnostic to Hyastenus. The inwardly curved tip of the rostral spine also characterizes this species. Distribution. Indo-West Pacific from Japan to the western Indian Ocean through Asian waters, with 15 – 35 m in depth. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF81FFBFF3E1CD7F5EAEF938.taxon	description	(Figs. 1 A – C, 2) Hyastenus calvarius Alcock, 1895, p. 213. ─ Alcock and Anderson, 1895, pl. 21 fig. 2. ─ Balss, 1938, p. 23. Thusaenys calvarius (Alcock): Griffin and Tranter, 1986, p. 193, figs. 65 d, 66 a – b. Material examined. Off Kwannon, Koror I., Palau Is., dredged; 1 ♂ (cb 6.7 × pcl 10.5 mm excluding posterior tubercle; rl 5.9 mm), NSMTCr 30959; June 17, 1980; K. Baba leg. ─ Entrance to Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 40 – 50 m in depth; 1 ♂ (5.4 × 8.8 mm; 4.5 mm), NSMT-Cr 30960; June 19, 1980; K. Baba leg. ─ Same locality, ca. 40 m in depth, coralline algae; 1 ♂ (5.4 × 8.2 mm; 4.7 mm), NSMT-Cr 30961; June 22, 1980; K. Baba leg. Remarks. The shape and armature of the carapace and rostrum agree in the two males examined without remarkable differences, being most characterized by the oblong, narrow and smooth carapace only with a vestigial epibranchial tubercle and a dorsally curved intestinal tubercle. This species was well explained as the type species of the new genus Thusaenys by Griffin and Tranter (1986), with the figures of the orbital region in ventral view and the G 1. The brief diagnostic notes on the present specimens are given in the following lines. The carapace surface is dorsally convex (Fig. 1 A, C) and shallowly separated into the gastric, cardiac and branchial regions. The rostral spines (Fig. 1 A – C) are only slightly longer than half the length of pcl, straight, horizontally directed forwards, and moderately divergent from the base. The supraorbital eave (Fig. 2 A) is thick, weakly curved dorsally and shallowly concave along the margin, with the anterior and posterior ends obtusely angulated. There are a deep U-shaped sinus and a prominent convexity behind the supraorbital eave (Figs. 1 A, 2 A); the postocular tooth is large and deeply cupped in dorsal, lateral and ventral views (Fig. 2 A – C). The antennal basal segment (Fig. 2 B) is thick and armed with an anterolateral tubercle, with the strongly convex outer margin. The third maxilliped (Fig. 2 D) has several strong teeth along the ischium inner margin and the strongly developed antero-external angle of the merus. The pterygostomial region is armed with two large teeth (Fig. 1 C). The G 1 (Fig. 2 E) is slender, with a row of long hairs, especially at the subterminal part. The terminal part (Fig. 2 F) is elongated, without hairs, agreeing well with the figures given by Griffin and Tranter (1986: fig. 66 a – b). Distribution. Known from some localities in Indonesian waters, Fiji, and the Andaman Islands; 36 – 120 m in depth. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF80FFBDF3C2CE405BB7F8DA.taxon	materials_examined	Material examined. Inside of Gesodokkuru Reef, off Arumonogui, Babelthuap I., Palau Is., dredged, ca. 20 m in depth, dead coral and sand; 1 ovig. ♀ (cb 7.5 × cl 9.9 mm), NSMT-Cr 30962; July 14, 1980; K. Baba leg. Remarks. The shape of the rostrum is characteristic in each of the known Micippa species. The frontal view of the rostrum of M. philyra was finely represented by Sakai (1938, fig. 45; 1976, fig. 138 a′) and Takeda et al. (2019, pl. 8 fig. E). Buitendijk (1939) well distinguished this species from the close congeners, M. thalia (Herbst, 1803) and M. platipes Rüppell, 1830. Synonyms of these three species, four for M. philyra, seven for M. thalia and five for M. platipes, are referred to Ng et al. (2008). Griffin and Tranter (1986) recorded many specimens from Indonesian waters, the Philippines, the Gulf of Thailand and the Iranian Gulf. Distribution. Indo-West Pacific from Japan southwards to Australia and then westwards to South Africa, from intertidal zone to the depth of about 50 m. Takeda (1973) recorded this species from the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF83FFBCF02CCD4C5861FC82.taxon	description	(Fig. 3 D – E) Material examined. Inside of Gesodokkuru Reef, off Arumonogui, Babelthuap I., Palau Is., dredged, ca. 20 m in depth, dead coral and sand; 1 ♂ (cb 4.8 × pcl 8.0 mm), NSMT-Cr 30963; July 14, 1980; K. Baba leg. Remarks. This unusual crab having dead twig appearance is not the majid, but definitely indicated as a monotypic species in the family Parthenopidae by the excellent study of Ng and McLay (2003) (cf. Remarks on Rhinolambrus turriger in this paper). In the specimen examined (Fig. 3 D – E), all the chelipeds and ambulatory legs are detached, and the distal part of the rostrum is broken off in front of the strong spine at the lower margin. However, there is no problem in the identification, with fine figures given by the original author (Alcock, 1895: pl. 3 fig. 1), Edmondson (1952: fig. 9), Griffin and Tranter (1974: fig. 2), Kensley (1977: figs. 1 – 2), Takeda and Marumura (1994: fig. 1), and Ng and McLay (2003). The G 1 and G 2 were illustrated by Griffin and Tranter (1974: fig. 2), and Ng and McLay (2003: fig. 6). Distribution. Japan, Hawaii and Taiwan in the West Pacific, the Andaman Islands, the Maldive Islands, and South Africa in the Indian Ocean, and the Red Sea, with bathymetric range from 16 to 90 m. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF82FFBCF3E7CB9F596DFC78.taxon	description	(Fig. 3 A – C) Material examined. Inside of Gesodokkuru Reef, off Arumonogui, Babelthuap I., Palau Is., dredged, ca. 20 m in depth; 1 ♂ (cb 11.4 × cl 11.3 mm including front and excluding posterior tubercles), NSMT-Cr 30964; July 13, 1980; K. Baba leg. ─ Entrance of Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 40 m in depth, mud; 1 ♂ (11.7 × 11. 8 mm), NSMT-Cr 30965; June 22, 1980; K. Baba leg. Remarks. As seen in Fig. 3 A – C, the chelipeds are remarkably long and slender, and there are two intestinal spines differing from only one spine in most of the congeners. These two characters are finely figured by Adams and White (1848: pl. 5 fig. 2), and shared only with Rhinolambrus sisimanensis which was originally described by Sèrene and Umali (1972) and later recorded by Davie and Turner (1994) as Parthenope (Rhinolambrus). These two species are generally close to each other, but readily distinguished by having one spine each at the gastric and branchial regions in R. turriger instead of two spines in R. sisimanensis. Borradaile (1903 b) made a simple but fine drawing to show adequately the specific characters. Flipse (1930) examined several specimens from Indonesian waters and deeply noted on the armatures of the carapace and chelipeds. In the paper dealing with Lambrachaeus ramifer Alcock, 1905, Ng and McLay (2003) showed the basic similarity between R. turriger and L. ramifer as the parthenopid crabs in having the long chelipeds and slender ambulatory legs of the parthenopid type, and decidedly transferred L. ramifer to the family Parthenopidae from the family Majidae s. l. Distribution. West Pacific from the Philippines to the Sunda Strait in the Java Sea, Darnley Island in the Torres Strait, and the Andaman Islands and Seychelles in the Indian Ocean (Miers, 1884; Flipse, 1930). The recorded bathymetric range is from 25 to 90 m. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF82FFB0F022CC22585CFB8F.taxon	description	(Figs. 4 – 6) urn: lsid: zoobank. org: act: D 0 E 0 AC 18 - 2 CC 4 - 465 B-BA 9 E- 9 C 6 D 0 A 69 F 5 F 8 Material examined. Kayangel Atoll, north of Babelthuap I., Palau Is., lagoon, dredged, 4 m in depth; 1 ♂ (cb 9.7 × cl 9.5 mm), holotype, NSMT-Cr 30966; July 6, 1980; K. Baba leg. Description of holotype. Carapace equilateral triangle in general outline; dorsal surface not strongly convex (Figs. 4 B, 5 A, 6 A); frontal region (Figs. 4 B, 5 A, C) deflexed, its dorsal surface concave between weakly convex supraorbital surface of both sides, rather longitudinally grooved, reaching posteriorly to transverse depression connecting posterior parts of both orbits; gastric region weakly convex, armed with pair of obtuse tubercles side by side at anterior part, obtuse tubercle of similar size at posterior median part, some smaller granules dispersed on entire surface. Submedian surface behind each gastric region distinctly depressed in front of cardiac region (Figs. 4 B, 5 A, 6 A). Anterior part of cardiac region raised, with small obtuse granules symmetrically arranged; posterior part more or less ridged transversely, with row of several obtuse granules. Intestinal region transverse in front of carapace posterior margin. Branchial region (Figs. 4 B, 5 A, 6 A, 5 D) prominent, curved, rather raised along carapace lateral margin. Front (Fig. 6 A – B) about one-third as wide as carapace between posterior ends of supraorbital margins of both sides, more or less lobular, slightly narrowing distally; distal half about equal to supraorbital eave in length; distal margin roundly truncated, with median one-third obtusely angulated as triangular tooth. Supraorbital eave (Fig. 6 A – B) with margin only weakly concave in dorsal view, weakly retreating posteriorly; dorsal surface convex dorsally; both of intercalated and external orbital teeth distinctly lobate, thin, each with rounded tip. Small tubercle just behind external orbital tooth. Carapace anterolateral margin short, longitudinal, unarmed. Branchial margin (Figs. 4 B, 5 A – B, 6 A) convex, slightly longer than carapace anterolateral margin, armed with several isolated, thin teeth; posterolateral margin with 2 or 3 tubercles. Third maxilliped (Figs. 5 B, 6 C) roughened, uneven, with obtuse tubercles of variable sizes; outer margin of merus nearly straight, with obtuse antero-external angle. Both chelipeds (Fig. 4) comparatively slender, about 2.2 times longer than carapace width, slightly different in shape. Merus subequal to palm in length, marginally armed with small tubercles of different sizes. Carpus short, with small tubercles. Left palm rather slender, with same thickness throughout length, but right palm stout as a whole, slightly thickened distally; tuberculation similar to both palms; 2 thin tubercles and 1 much stronger tubercle at basal and distal parts of upper margin, respectively; outer surface roughened with small conical granules and longitudinal row of granules in midline. Fingers of left chela small, but those of right chela thick, leaving wide gap between both fingers. All ambulatory legs missing. Pleon (Fig. 5 B) wholly roughened with granules; third to fifth pleonites fused; fifth and sixth pleonites with subparallel lateral margins; telson nearly triangular in general outline, with sharp tip. G 1 (Fig. 6 D) stout, tapering distally, with terminal part flattened, weakly curved, semitransparent, hairy. Remarks. The wide and weakly deflexed front with a dorsal longitudinal depression is somewhat similar to those of the Rhinolambrus species such as R. lamelliger (White, 1847) [White, 1847 a – b, as Lambrus lamelliger sp. nov.; Adams and White, 1848, as Lambrus lamellifrons; Rathbun, 1906, as Parthenope (Rhinolambrus) lamelligera; Dai et al., 1986, Dai and Yang, 1991, as P. (R.) lamellifrons; Takeda and Marumura, 2019, as R. lamelliger], and R. pelagicus (Rüppell, 1830) [Rüppell, 1830, as Lambrus pelagicus sp. nov.; A. Milne-Edwards, 1872, as L. affinis sp. nov.; Rathbun, 1907, as Parthenope (Parthenope) melana sp. nov.; Flipse, 1930, as L. (R.) latifrons sp. nov.]. However, in the species of the genus Rhinolambrus A. Milne-Edwards, 1878, the gastric, cardiac, intestinal and branchial regions are strongly bulged and armed with some strong and sharp tubercles, and the hepatic region has a distinctly produced conical tooth on the carapace anterolateral margin between the external orbital angle and the branchial margin; these characters are not possessed by the present specimen. As frequently remarked in some precedent papers, the genus Pseudolambrus, to which the present new species is referred, is heterogenous, with the various external appearance of the known species. The present new species is without doubt most close to P. sundaicus Ng and Rahayu, 2000, which was originally described from Jakarta Bay, Java, Indonesia, and additionally recorded from Okinawa-jima Island in the Ryukyu Islands by Maenosono (2016). In both papers, the fine photographs of the specimens were given for the adequate comparison with the present new species. Pseudolambrus palauensis sp. nov. has the sloping shoulders of the carapace branchial margins, with the laterally angulated branchial margin (Figs. 4 B, 5 A – B, 6 A), whereas in P. sundaicus, the brachial margin is regularly convex and nearly longitudinal behind the shoulder. In the new species, the external orbital and intercalated teeth are distinctly flattened and directed outward, and thus the orbit seems to be somewhat opened and imperfect, but in P. sundaicus, both the teeth are directed forward and tightly close to make complete orbit. There is a small tubercle just behind the external orbital tooth in the new species, but in P. sundaicus, such a small tooth is absent at the place with the long-necked appearance. In the new species, the antero-external angle of the third maxilliped merus is produced and weakly angulated, instead in P sundaicus, it is distinctly rounded. The G 1 of the new species is weakly flattened at the distal part, but that of P. sundaicus is subtruncated at the tip. Etymology. The new species named after the type locality, the Palau Islands. Distribution. Known only by the holotype male from the Kayangel Atoll, north of Babelthuap Island in the Palau Islands, 4 m in depth.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8EFFB7F22BCCF25B18FCE1.taxon	materials_examined	Material examined. Kayangel Atoll., north of Babelthuap I., Palau Is., lagoon, dredged, 4 m in depth; 1 ♂ (cb 4.8 × cl 3.9 mm), NSMT-Cr 30967; July 6, 1980; K. Baba leg. ─ Entrance of Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 40 m in depth, mud; 1 ♀ (10.1 × 7.9 mm), NSMT-Cr 30968; June 22, 1980; K. Baba leg. Remarks. There are many records of this species from the whole Indo-West Pacific, with some generic and subgeneric names such as Lupea by H. Milne Edwards (1834), Achelous by A. Milne-Edwards (1861), Portunus (Achelous) by Rathbun (1911), Neptunus (Achelous) by Alcock (1899), Gordon (1938), and Sakai (1939), Cycloachelous by Ward (1942), Portunus by Stephenson and Campbell (1959), Crosnier (1962), Sakai (1965), Dai and Yang (1991), and Apel and Spiridonov (1998), and Portunus (Cycloachelous) by Sakai (1976). These records are, however, not always reliable, with certain anxiety about the confusion with two closely related species, Cycloachlous orbitosinus (Rathbun, 1911) and C. levigatus Koch, 2021, and also with another species, C. octodentatus (Gordon, 1918). Koch (2021) made the detailed comparison of the new species, C. levigatus, with C. orbitosinus and C. octodentatus. Then, Koch et al. (2022) further discussed the systematic status of the genus based on the morphological and molecular analyses and showed the presence of nine congeneric species. These three species are also similar to C. granulatus (H. Milne Edwards, 1834) in the shape, dorsal areolation and anterolateral armature of the carapace. Apel and Spiridonov (1998) used the characters to distinguish C. granulatus from C. orbitosinus in the key that ʺLast anterolateral tooth not larger than other teeth; carapace granules are not grouped in patches but almost cover entire surface; under side of manus without longitudinal furrow along most of its length; lateral borders of second abdominal segment in both sexes without dorsally directed spiniform process; Go / 1 short and stout with flared tip. ʺ The pleons of both sexes of C. orbitosinus and C. levigatus, and the male pleon of C. octodentatus were clearly shown by Koch (2021), and the male pleon of C. granulatus by Koch et al. (2022). The lateral margins of the sixth pleonite are straight or weakly curved in C. granulatus, whereas strongly convex in C. orbitosinus and C. levigatus, and rather angulated in C. octodentatus. Furthermore, the additional definitive difference is that the pleonal surfaces of both sexes are characteristically sculptured in C. oribitosinus and smooth in the other three species. Considering these distinguishing characters, the male and female specimens examined, though young, are safely referred to C. granulatus. Distribution. The type locality of C. levigatus is Nhatrang Bay, Vietnam, and the other localities in the literature confirmed by the original author are the Philippines (Stephenson and Rees, 1967, as Portunus orbitosinus) and Japan (Sakai, 1939, as Neptunus (Achelous) orbitospinis; 1965, as P. orbitospinus; 1976, as P. (Cycloachelous) orbitosinus). The following conclusive comments on the distribution were recorded by the original author; C. levigatus localities are in East or Southeast Asian waters, in comparison with C. orbitosinus from the western Indian Ocean. The type locality of C. octodentatus is Singapore, while the present species is widely distributed in the whole Indo-West Pacific at the depth of 30 to 120 m.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF89FFB7F3CECBBA5B06FA12.taxon	materials_examined	Material examined. Off Kuwannon, Koror Is., Palau Is., dredged, with coralline algae; 1 ♂ (cb 15.8 × cl 10.0 mm), 1 ♀ (11.6 × 7.6 mm), NSMT-Cr 30969; June 17, 1980; K. Baba leg. Remarks. This species is the commonest among the Thalamita species having two lobedfront, being characterized by the basal antennal segment armed with a crest fringed with sharp granules as figured by Wee and Ng (1995). Many synonyms of this species including Thalamita dispar Rathbun, 1914, were discussed in detail by Stephenson and Rees (1967). Distribution. Many records of occurrence in the whole Indo-West Pacific, from tidal flats to shallow waters.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF89FFB7F3E2CE2A5E02FC37.taxon	description	(Fig. 7 E – F)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF89FFB7F3E2CE2A5E02FC37.taxon	materials_examined	Material examined. Off Kuwannon, Koror Is., Palau Is., dredged, with coralline algae; 1 ♂ (cb 12.6 × cl 8.2 mm), NSMT-Cr 30970; June 17, 1980, K. Baba leg. ─ Entrance of Toagle Mid in Arangel Channel, Babelthuap I., Palau Is., 40 m in depth, mud; 1 ♂ (8.6 × 6.0 mm), NSMT-Cr 30971, 1 ♂ (12.4 × 8.4 mm), 1 ovig. ♀ (11.7 × 8.1 mm), NSMT-Cr 30972; June 22, 1980; K. Baba leg. ─ Inside of Gesodokkuru Reef off Arumonogui, Babelthuap I., Palau Is, dredged, ca. 20 m in depth; 1 ovig. ♀ (11.1 × 7.2 mm), NSMT-Cr 30973; July 13, 1980; K. Baba leg.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF89FFB7F3E2CE2A5E02FC37.taxon	discussion	Remarks. This species was briefly characterized by Wee and Ng (1995), with figures, being most characterized by the weakly arched front divided into two by a small median notch (Fig. 7 E – F). The carapace dorsal ridges are also simply but clearly shown by Crosnier (1962), with a pair of the frontal, mesogastric, metagastric, epibranchial and mesobranchial ridges, but no cardiac ridge (Fig. 7 E – F).	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF89FFB7F3E2CE2A5E02FC37.taxon	distribution	Distribution. Indo-West Pacific from the Red Sea and Madagascar to Australia, Tahiti, and the Ryukyu Islands. The occurrence in the Ryukyu Islands is referred to Nagai and Nomura (1988); the definite locality was not recorded, but the identification is acceptable for the photograph in the filed. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF89FFB5F02BCC0758A3F9EA.taxon	description	(Fig. 7 A – B)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF89FFB5F02BCC0758A3F9EA.taxon	materials_examined	Material examined. Inside of Gesodokkuru Reef off Arumonogui, Babelthuap I., Palau Is., dredged at ca. 20 m in depth; 1 ♀ (cb 10.8 × cl 7.4 mm), NSMT-Cr 30974; July 13, 1980, K. Baba leg. Remarks. De Man (1926) examined one of the syntypes of Thalamita admeta var. intermedia Borradaile, 1903, to ascertain the taxonomic validity of his new species, Thalamita bilobata, and mentioned that both are different from each other most remarkably in the number of the teeth on the antennal basal segment. Wee and Ng (1995) discussed the taxonomic identity of some varieties of T. admete (Herbst, 1803) defined by Borradaile (1903 a), and concluded that one of them, var. intermedia, is specifically distinct from T. admete. However, the corrected specific name, T. intermedia, was preoccupied by T. intermedia Miers, 1886, and thus the new name, T. borradailei was proposed by Wee and Ng (1995). Later, Apel and Spiridonov (1998), who examined the syntypes of T. admeta var. intermedia and many specimens from the Indian Ocean and the West Pacific, concluded that T. borradailei falls into the size / age-related variation, accepting the tentative synonymisation of T. admete var. intermedia as proposed by Stephenson and Hudson (1957).	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF89FFB5F02BCC0758A3F9EA.taxon	distribution	Distribution. Widely distributed in the Indian Ocean, and also known from Indonesia, the Philippines, the Palau Islands, Australia, and French Polynesia in the Pacific, 5 – 25 m in depth.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8BFFB5F3CECE525EACFD2A.taxon	description	(Fig. 7 H) Material examined. Off Kuwannon, Koror Is., Palau Is., dredged, with coralline algae; 1 ovig. ♀ (cb 9.0 × cl 6.3 mm), 1 ♀ (11.0 × 7.8 mm), NSMTCr 30975; June 17, 1980, K. Baba leg. Remarks. This species is characteristic in having the weakly convex four-lobed front, and the outer lobe being about twice the length of the inner lobe (Fig. 7 H). Of the five anterolateral teeth of the carapace, the first or the external orbital tooth is much larger than the following teeth, and the fourth tooth is smallest and almost obsolete (Fig. 7 H). The details of the carapace dorsal ridges are finely shown by Crosnier (1962), Takeda (1989 a), and Wee and Ng (1995). Distribution. The Pacific Ocean from Hawaii and Japan to Australia, and the Indian Ocean from the Andaman Sea to Madagascar, with 15 – 80 m in depth. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8BFFB4F1EBCB775B14FC78.taxon	description	(Fig. 7 C – D)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8BFFB4F1EBCB775B14FC78.taxon	materials_examined	Material examined. Inside of Gesodokkuru Reef off Arumonogui, Babelthuap I., Palau Is, dredged, ca. 20 m in depth; 1 ♂ (cb 7.6 × cl 5.9 mm), NSMT-Cr 30976; July 13, 1980; K. Baba leg. Remarks. Evans (2018) showed with the molecular analysis that the genus Thalamonyx is valid and generically distinct from the genus Thalamita. The genus Thalamonyx is represented by Goniosoma danae A. Milne-Edwards, 1869 (type species) and Thalamonyx gracilipes A. Milne-Edwards, 1873 (present species), both of which are close to each other in the general formation of the carapace, chelipeds and ambulatory legs. According to Stephenson and Rees (1967), the most conspicuous difference between the two species is the presence of four ridges in an arc on the mesobranchial and cardiac regions in Thalamonyx gracilipes, instead of no ridges on the cardiac region in T. danae. The frontal region (Fig. 7 C) is strongly developed forwards as a plate, with the weakly sinuate margin divided into two lobes by a median minute notch, followed laterally with a large and oblique orbit at each side. The external orbital or first anterolateral tooth is much larger than the following four subequal teeth (Fig. 7 C). The telson of the male pleon strongly tapers and has a sharp tip (Fig. 7 D). The G 1 is represented by Stephenson and Rees (1967), with which the G 1 of the present male agrees well in having the curled setae at the distal part. Distribution. The records of occurrence are not many, only with several localities in the wide area of the Indo-West Pacific, without intervening localities (Hawaii, New Caledonia, Tonga, Cocos Keeling Island, the Andaman Islands, and Madagascar), 12 – 77 m in depth. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8AFFB4F23DCC225EB0FBA8.taxon	description	(Figs. 8, 10 A, 15 F – G)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8AFFB4F23DCC225EB0FBA8.taxon	materials_examined	Material examined. Entrance to Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 30 – 40 m in depth, with coralline algae; 1 ♂ (cb 12.6 × cl 8.7 mm), NSMT-Cr 30977; June 19 1980; K. Baba leg.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8AFFB4F23DCC225EB0FBA8.taxon	discussion	Remarks. This species is most characteristic in having only four strong and sharp anterolateral teeth of the carapace including the external orbital tooth (Figs. 8 A, 10 A); posterior three teeth are only slightly smaller than the first or the external orbital tooth. All the ridges of the carapace areolae are distinct (Figs. 8 A, 10 A). The frontal margin is cut into four lobes (Figs. 8 A, 10 A); each median lobe about two-thirds as wide as the lateral lobe, its outer end being shortly overlapped by the lateral lobe; the lateral lobe is slightly behind the frontal level of the median lobe, weakly concave in the middle, making the appearance of the six-lobed front. The frontal and supraorbital margins are narrowly crested along the whole lengths (Fig. 10 A). The antennal basal segment is armed with a distinct ridge tipped with small granules along the distal half. The third maxilliped is as figured, with the anterodistal angle of the merus is narrowly extended forward (Fig. 15 F). The male pleon is comparatively wide, with the bulged sixth pleonite (Fig. 8 B). Both chelipeds are somewhat different in size and shape (Fig. 8 C – D); the surfaces of the carpus and palm are of somewhat squamous appearance with depressed granules of variable sizes; the fingers are strongly and irregularly toothed throughout the lengths of both cutting edges. The G 1 was roughly figured by Stephenson and Hudson (1957: fig. 2 K) and in the present paper (Fig. 15 G); the shaft is stout, parallel-sided throughout the length, strongly curved at the middle.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8AFFB4F23DCC225EB0FBA8.taxon	distribution	Distribution. The Great Barrier Reef; Rongelap and Bikini Atolls in the Marshall Islands, 45 – 55 m in depth. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF8AFFAAF1C1CCF25AEAFB67.taxon	description	(Fig. 7 G) Material examined. Kayangel Atoll, north of Babelthuap I., Palau Is., lagoon, dredged, 4 m in depth; 1 ♂ (cb 17.6 mm including epibranchial tubercles × cl 7.1 mm), NSMT-Cr 30978; 3 ♂♂ (10.2 × 4.9 mm ─ 19.5 × 8.5 mm), 1 juv., NSMTCr 30979; July 6, 1980; K. Baba leg. Remarks. The taxonomical and nomenclatural problems of the Portunus / Xiphonectes longispinosus complex were resolved by Spiridonov (2016) who checked many synonymous species, examined the syntypes of Amphitrite longi-spinosa Dana, 1852, and established X. tuerkayi sp. nov. distinct from X. longispinosus s. str. As a male (NSMT-Cr 30978) among four males and one juvenile in the present specimens was shown in Fig. 7 G, the epibranchial spine is remarkably long, nearly half of the cb; the lateral end of the carapace posterior margin is strongly angulated; the frontal margin is four-lobed, with two small median lobes; and the merus and palm of the cheliped are slender and elongated. These characters agree with the figure given by Crosnier and Thomassin (1974) and also with a photograph given by Sakai (1939), and seem to be somewhat different from the photographs given by Rathbun (1906) and Edmondson (1954) in the armature of the carapace anterolateral teeth and the length of the epibranchial tooth, and the length and stoutness of the chelipeds. Nagai (1981) recorded a male from Wakayama Prefecture in the Pacific coast of central Japan; that illustration is similar to the photograph given by Sakai (1939) except for the slightly stouter chelipeds. The present specimen having the extremely slender chelipeds is referred just to X. longispinosus sensu Sakai (1939). Distribution. The X. longispinosus complex is known from the wide area of the Indo-West Pacific, but the species referred to X. longispinosus sensu Sakai (1939) is reliably known only from Japan and Madagascar. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF94FFAAF3A3CD1A5919FB8F.taxon	materials_examined	Material examined. Off Kwannon, Koror I., Palau Is. dredged; 1 ovig. ♀ (cb 4.8 × cl 3.2 mm), NSMT-Cr 30980, 1 juv., 1 ovig. ♀ (10.3 × 7.0 mm), 1 ♀ (8.9 × 6.1 mm), NSMT-Cr 30981; June 17, 1980; K. Baba leg. Remarks. This species is generally close to Chlorodiella laevissima (Dana, 1852), but as mentioned in the original description and by Maenosono (2022), it is readily distinguished from C. laevissima by having only four anterolateral teeth of the carapace including the external orbital tooth. The external orbital tooth may be united with the real first tooth that is seemingly the second tooth in the other species except for C. barbata (Borradaile, 1900) and C. quadrilobata Dai, Cai and Yang, 1996. These two species are characterized each by a tuft of soft hairs at the bases of the fingers and the lobate anterolateral carapace teeth, respectively. The G 1 of this species was represented in the original description by Miyake and Takeda (1968), being truncated at the tip surrounded by some short setaceous tubercles as cited in this paper (Fig. 10 E). Distribution. This species was originally described on the specimens from Ngarsmau, Babldáob Island, Palau Islands, 26 m in depth, and then recorded from the Ryukyu Islands, the Philippines, Viet Nam, the Caroline Islands, the Marshall Islands, and the Great Barrier Reef, Australia.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF94FFA8F1F5CCAF58BFFCE0.taxon	description	(Figs. 9 F, 10 B – C)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF96FFA8F390CBBA5E6EFDD8.taxon	description	(Fig. 9 A) Material examined. Off Kwannon, Koror, Palau Is., dredged, with coralline algae; 1 ♂ (cb 8.8 × cl 6.6 mm), NSMT-Cr 30985; June 17, 1980; K. Baba leg. ─ Inside of Gesodokkuru Reef, off Arumonogui, Babelthuap I., Palau Is., dredged, ca. 20 m in depth, dead coral and sand; 1 ovig. ♀ (9.0 × 7.0 mm), NSMT-Cr 30986; July 13, 1980; K. Baba leg. Remarks. The specimens examined agree with the photographs given by Guinot (1976) who established the genus Gaillardiellus for Cancer (Aegle) rüppellii Krauss, 1843 [= Actaea rueppellii] and allied three species, Actaea Alphonsi Nobili, 1905, A. ruppelli var. orientalis Odhner, 1925 [= A. orientalis] and A. superciliaris Odhner, 1925. Then, Davie (1997) described a new species, G. bathus from New Caledonia, 270 – 312 m in depth, which was later recorded by Takeda and Webber (2006) from the Kermadec Islands, 80 – 162 m in depth. Otherwise, Takeda (1997) and Takeda and Komatsu (2018) insisted that Actaea bocki Odhndr, 1925 should be transferred to Guillardiellus. The colored photographs of G. rueppellii were given by Mendoza et al. (2014) and Takeda and Komatsu (2018) based on the specimens from the Cocos Keeling Islands and the Ogasawara Islands, respectively. In the present specimen long preserved in the spirit, the blackish color of the bristles is entirely faded out. Distribution. Not uncommon in the whole Indo-West Pacific, 50 – 105 m in depth.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF96FFA8F022CA425E20F9A0.taxon	description	(Fig. 9 B) Metaxanthops acutus Serène, 1984, p. 214, fig. 129, pl. 30 figs. D – E. ─ Ng and Clark, 2002, p. 535, fig. 3 b. Material examined. Off Kwannon, Koror I., Palau Is., dredged, with coralline algae; 2 ♂♂ (cb 6.8 × cl 5.5 mm; 5.2 × 4.1 mm), NSMT-Cr 30987; June 17, 1980; K. Baba leg. Remarks. Both specimens examined agree well with the photographs of the type specimens from Madagascar and the Comoro Islands (Serène, 1984: pl. 30 figs. D – E) and also with the photograph of a male from New Caledonia (Ng and Clark, 2002: fig. 3 b). Although Ng and Clark (2002) doubted its identity due to the occurrence at the locality far from the type locality, there seems to be no doubt for the identification as far as the comparison of the photographs concerned. Distribution. So far known from the literature, the known localities are, as recorded above, in the western Indian Ocean and southern Pacific, and now from the Palau Islands. Serène (1984) recorded that both of the type specimens were collected at the intertidal zone, but the New Caledonian specimen was collected at the depth of 51 m in the lagoon. As for the present specimens, there is no depth record on the label, but the dredging was made in the sea shallower than 40 m in depth similar to the other sampling stations. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF91FFAEF38CCD2A5B14FE8A.taxon	description	(Figs. 10 F, 11 A – B) Material examined. Off Kwannon, Koror I., Palau Is., dredged, with coralline algae; 1 ♂ (cb 5.1 × cl 4.1 mm), NSMT-Cr 30988, 1 ovig. ♀ (5.8 × 4.9 mm), NSMT-Cr 30989, 1 ♂ (5.2 × 4.4 mm), 1 ovig. ♀ (5.1 × 4.1 mm), NSMT-Cr 30990; June 17, 1980; K. Baba leg. Remarks. In these specimens (Fig. 11 A – B) long preserved in spirit, the color pattern is still traceable; the frontal margin and the anterior halves of both lateral margins of the carapace are dark brown bordered with a whitish line along the inside margins. The transverse whitish line behind the frontal dark brown is extended laterally onto the eyestalk. The carapace shape and color pattern agree with the photographs by Serène (1984, pl. 40 fig. E., as T. glaberrima obscura), Galil (1988, fig. 1 c) and Castro (1997, pl. 1 fig. D), and also with the vivid color photographs given by Maenosono (2017, fig. 8 C – D) who checked the accuracy of records in various publications and research papers on the basis of the color pattern. Castro (1997) examined many specimens from many localities and designated the neotype for the subsequent taxonomic studies. The G 1 is fringed with setose hairs along both sides as seen in Fig. 10 F and agrees generally with rough sketch given by Galil (1988, fig. 2 f), but is not strictly comparable with it. Distribution. This species is generally associated with pocilloporid corals widely distributed in the Indo-West Pacific from Japan to Australia, New Caledonia, and Madagascar. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF90FFAEF39EC9FB5E7DFB4A.taxon	description	(Fig. 11 C – E)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF90FFAEF39EC9FB5E7DFB4A.taxon	materials_examined	Material examined. Entrance to Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 40 – 50 m depth, mud; 1 ♂ (cb 5.0 × cl 3.3 mm), NSMT-Cr. 30991; June 19, 1980; K. Baba leg. Remarks. The smooth, transversely quadrangular carapace of the male shows without doubt its suitable taxonomic position in the genus Notonyx. All of the known 12 species are small in size, less than cb 10 mm, and closely resemble to each other in the carapace, chelipeds and ambulatory legs. Their general morphological differences are sometimes subtle, but based on close observation, there may be constant differences in the shape of the carapaces, and the G 1 shape is the most important character to distinguish each species. Ten species described intensively during recent some years by Clark and Ng (2006, 2011), Ng and Clark (2008, 2010), Naruse and Maenosono (2009), Naruse and Takeda (2010), Rahayu and Ng (2010 a, b), and Rahayu (2011) are mostly well described with the figures and photographs, but the status of the type species, N. nitidus A. Milne-Edwards, 1873, from New Caledonia still remains unclear. Quite unfortunately, the male specimen examined lacks the pleon together with the G 1, and also all the ambulatory legs are absent in a specimen vial. The general shape of the carapace seems to be close to N. sagittifer Ng and Clark (2010) from Mindanao, the Philippines, which was compared with N. latus Ng and Clark, 2008, from the Lesser Sunda Islands. The holotype specimen of N. sagittifer is a male previously identified as N. nitidus by Serène and Umali (1972). The general shape of the carapace (Fig. 11 C) seems to be closer to N. sagittifer rather than the other congeneric species, but the identification of the specimen at hand is not always definitive because of lacking the male G 1. The ratio of the carapace breadth to length is 1.28, and the carapace anterolateral margin is only weakly convex outwards. Both chelipeds are compressed in dorsal view (Fig. 11 E) and each palm is wholly glabrous, with the keeled lower margin (Fig. 11 D). The male G 1 is needed for the definite identification. Distribution. The Notonyx species are reported from the limited localities, probably due to the special habitat in shallow water grass bed with sand and gravel substrates. As mentioned by Rahayu (2011), four species are exclusively known from Indonesian waters; two species from the Philippines; each one species from the Andamans, Thailand, Fiji, New Caledonia and Japan; only N. kumi Naruse and Maenosono, 2009, has been reported from the distant localities, the Ryukyu Islands in Japan and the Lesser Sunda Islands in Indonesia. The present record of the genus is new to Micronesian waters.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF90FFACF1E5CD345877FC78.taxon	description	(Fig. 9 C)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF90FFACF1E5CD345877FC78.taxon	materials_examined	Material examined. Entrance to Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 30 – 40 m in depth, with coralline algae; 1 ovig. ♀ (cb 5.2 × cl 4.0 mm), NSMT-Cr 30992; June 19, 1980; K. Baba leg. Remarks. This small ovigerous female agrees well with the female holotype and two male paratypes found in stomach contents of roundspot goatfish / sidespot goatfish, Parupeneus pleurostigma (Bennett) from the Ogasawara Islands. In the original description, otherwise, a male from Tanega-shima Island in the south of Kyushu was also recorded as the paratype. In the specimens from the Ogasawara Islands as well as the present ovigerous female, the carapace dorsal surface is ornamented only with a transverse row of six, weakly raised, bare areolets behind the front-orbital margin. Takeda and Marumura (1995 b), however, mentioned on the variations of the areolets on the carapace dorsal surface in three Japanese localities. In the specimens from the Kii Peninsula and Tanega-shima Island, the carapace dorsal surface is ornamented, in addition to six areolets behind the front-orbital margin, with two transverse rows of four and three areolets at level of the gastric and cardiac regions, respectively; in a female from Ie-jima Island in the Ryukyu Islands, it is almost impossible to locate the posterior seven areolets. The carapace anterolateral margin is armed with three tubercular teeth tipped each with a short stiff seta; the third tooth is similar to, but much smaller than the first and second teeth. The genus Lophoplax is composed of L. bicristata Tesch, 1918, L. sculpta (Stimpson, 1858), L. takakurai Sakai, 1935, and L. sextuberculata Takeda and Kurata, 1984, because L. teschi Serène, 1971 was transferred to Serratocoxa Ng, 1987 and then to Cryptolutea Ward, 1936 (Ng et al., 2008). Takeda and Kurata (1984) and Takeda and Marumura (1995 b) considered that Pseudocryptocoeloma symmetrinudus Edmondson, 1951, is to be transferred to Lophoplax, but at present, Pseudocryptocoeloma is considered to be generically distinct from Lophoplax, with two species, P. parvus Ward, 1936 (type species) from Queensland, Australia, and P. symmetrinudus from Samoa and the Ryukyu Islands (Edmondson, 1951; Marumura and Takeda, 2012; Maenosono, 2019). Distribution. Previously known only from Japanese waters (Kii Peninsula, Wakayama Prefecture, 80 – 100 m in depth; Tanega-shima Island, ca. 70 m in depth; Ie-jima Island in the Ryukyu Islands, 70 m in depth; Ogasawara Islands), and now the Palau Islands, 30 – 40 m in depth.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF92FFACF387CC225E29FA57.taxon	description	(Fig. 12 A – C)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF92FFACF387CC225E29FA57.taxon	materials_examined	Material examined. Entrance to Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 40 m depth, mud; 1 ♀ (cb 8.6 × cl 5.8 mm), NSMT-Cr 30993; June 22, 1980; K. Baba leg. Remarks. The genus Typhlocarcinops was thoroughly revised by Ng and Rahayu (2020) who revalued the synonymity and described nine new species in addition to 13 species known at that time. The authors illustrated and described all the species based on many additional specimens and the type specimens of the known species. The real images of the species described by Rathbun (1909, 1914) were made clear, but the identification of some species is not always easy due to the variability with sexes, developmental stages and individuals. Especially, the proportion and convexity of the carapace, and the lobulation of the carapace anterolateral margin still come into question. The female examined agrees mostly with the diagnoses of T. decrescens given by Ng and Rahayu (2020) who examined the type specimens (holotype male and paratype three males and two females from the Philippines) and two males and two females from the South China Sea, and a male from the Arafura Sea, and made clear the variations about the carapace proportion and anterolateral armature. In the present female (Fig. 12 A), the carapace is 1.48 times broader than long and seems to be proportionally wider than seven males and three females among the specimens recorded by Ng and Rahayu (2020), in which the proportion falls mostly in 1.21 – 1.38; the exceptional proportion exceeding this numerical value is only in a female from Shandung in China, with 1.43. The carapace of the female examined is wider than the recorded specimens, but the proportion of the carapace is variable and not always definitive character in this genus to distinguish the congeneric species as well as the front-orbital region and carapace posterior part (Fig. 12 B – C). Distribution. Japan, the Philippines, the South China Sea, and Indonesia, 22 – 29 m in depth. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF92FFA2F02DCDC45E5EFA12.taxon	description	(Fig. 9 D)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF92FFA2F02DCDC45E5EFA12.taxon	description	Vellumnus pygmaeus (Takeda): Takeda and Komatsu, 2018, p. 181, fig. 6 G. Material examined. Inside of Gesodokkuru Reef, off Arumonogui, Babelthuap I., Palau Is., dredged, ca. 20 m in depth; 1 ♂ (cb 5.7 × cl 4.5 mm), NSMT-Cr 30994; July 13, 1980; K. Baba leg. Remarks. Ng (2010) referred three Pilumnus species (P. vermiculatus A. Milne-Edwards, 1873, P. labyrinthicus Miers, 1884 and P. penicillatus Gordon, 1930) and two Planopilumnus species (P. minabensis Sakai, 1969 and P. pygmaeus Takeda, 1977) to his new genus Vellumnus. All the species have typical Pilumnus - type characters, but are distinctive in having the clearly-patterned symmetrical areolets or labyrinth-like pattern of setae on the carapace. Of five known species, V. labyrinthicus, V. penicillatus and V. pygmaeus are generally close to each other in having the labyrinth-like pattern of setae, but their patterns are distinctly different from each other: Miers (1884) and Ng (2010) for V. labyrinthicus; Gordon (1931) for V. penicillatus; Takeda (1977) and Takeda and Komatsu (2018) for V. pygmaeus. The specimen at hand agrees well with V. pygmaeus, especially in having the heartshaped protogastric region, although the epigastric regions of both sides are distinctly isolated by a median longitudinal groove from the median incision of the front. Distribution. Vellumnus pygmaeus is known from the Ogasawara Islands, 41 – 105.6 m in depth, and now from the Palau Islands, ca. 20 m in depth, as new to Micronesian waters.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF9CFFA1F1E9CE0E5BA3FA57.taxon	materials_examined	Material examined. Entrance to Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 40 – 50 m in depth, mud; 1 ♂ (cb 3.5 × cl 2.9 mm), NSMT-Cr 30995, 1 ♀ (4.0 × 3.1 mm), NSMT-Cr 30996; June 19, 1980; K. Baba leg. Remarks. The genus Microtopsis is composed of two species, the type species, M. takedai Komai, Ng and Yamada, 2012, described on one male and two females from Okinawa Island in the Ryukyu Islands, 12 – 30 m in depth, and another species, M. teschi Ng and Castro, 2016, from the northwest of the Kei Islands, Indonesia, 90 m in depth. They are remarkably small, with the carapace breadth 3.1 – 3.6 mm in M. takedai and 1.9 – 2.1 mm in M. teschi, but well described and figured by the original authors of both species. According to Ng and Castro (2016), M. teschi is distinguished from M. takedai by the features that the carapace dorsal surface is covered with small granules (rather smooth in M. takedai), the anterior part of the carapace lateral margin is fringed with spiniform granules (small blunt granules in M. takedai), the male telson is triangular in shape (rather semicircular in M. takedai), the male sixth pleonite is proportionally broader than in M. takedai), and the G 1 is proportionally longer, with the median twist more substrantial and the tip more hook-shaped than in M. takedai. The figures of the present specimen (Figs. 12 D – G, 13) agree well with the characters of M. teschi given by Ng and Castro (2016). Distribution. As mentioned above, this species was originally reported from the northwest of the Kei Islands, Indonesia, 90 m in depth. This is the second report of this small species, and new to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF9FFFA1F3CFCE2A5EAEF8DA.taxon	description	(Figs. 14 C – F, 15 C – E)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF9FFFA1F3CFCE2A5EAEF8DA.taxon	materials_examined	Material examined. Inside of Gesodokkuru Reef, off Arumonogui, Babelthuap I., Palau Is., ca. 20 m in depth, dead coral and sand; 1 ♂ (cb 8.2 × cl 7.3 mm), NSMT-Cr 30997, 1 ovig. ♀ (8.7 × 7.6 mm), NSMT-Cr 30998; July 13, 1980; K. Baba leg. ─ Same locality, 1 ovig. ♀ (6.7 × 5.5 mm), NSMT-Cr 30999; July 14, 1980; K. Baba leg. Remarks. In the specimens examined, most of the chelipeds and ambulatory legs are detached, but the carapaces are good in condition. The carapace (Fig. 14 C, F) is depressed as a whole, with rounded quadrilateral outline; the carapace posterolateral corner, about one-third the carapace lateral margin, is concave; the carapace dorsal regions are divided by shallow and smooth depressions and covered with scaly granules of various sizes. The front is prominent, with two smoothly convex lobes. The merus of the third maxilliped (Fig. 15 C) is developed as a narrow lobe, with rounded distal margin, and concave along the inner margin to receive the base of the carpus. The G 1 is illustrated by Moosa and Serène (1981) and Castro (2000) and enough to know the basic formation with the subterminal bulb and small branch about half as long as the acute terminal process. As the figures are somewhat variable according to the observation angles, the G 1 is again illustrated in this paper (Fig. 15 D – E). The G 1 s of this species and closely allied species, N. contractus (Rathbun, 1902) were shown by Castro (2000) who arranged the morphological differences between the two species in the table. Distribution. As mapped and tabulated by Castro (2000) who examined numerous specimens from many localities, the geographical range is wide in the Indo-West Pacific from Madagascar and the Red Sea to Australia and New Caledonia, and northwards to Japan through Indonesian waters, the South China Sea, and the Philippines, 10 – 146 m in depth. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF9EFFA6F3C5CE875B7DF938.taxon	description	(Figs. 14 A – B, 15 A – B)	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF9EFFA6F3C5CE875B7DF938.taxon	materials_examined	Material examined. Off Kwannon, Koror I., Palau Is., dredged, with coralline algae; 1 ♂ (cb 7.0 × cl 4.7 mm), NSMT-Cr 31000; June 17, 1980; K. Baba leg.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF9EFFA6F3C5CE875B7DF938.taxon	discussion	Remarks. Both chelipeds, three pairs of the right ambulatory legs and the left third or fourth leg, and both of the reduced last pereopods are missing in the male at hand. However, it is safely identified as Palicoides whitei due to the detailed morphological differentiation from another representative of the genus, P. longimana (Miyake, 1936), based on numerous specimens by Castro (2000). The sculpture of the carapace dorsal surface is characteristic as shown in Fig. 14 A. The distal part of the eyestalk is strongly developed as a curved tubercle to protect the cornea, indicated with arrow in Fig. 15 A. The G 1 of the present male agrees with the figures given by Calman (1900), Moosa and Serène (1981) and Castro (2000), in having the bifurcated distal part with the long and short flattened processes. In the present specimen, the G 1 is typical in having the distal long process directed forward (Fig. 15 B). Castro (2000) showed that the marginal armature of the processes becomes more complex in the specimens of larger sizes.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
1B153E3AFF9EFFA6F3C5CE875B7DF938.taxon	distribution	Distribution. The known localities are shown on the map by Castro (2000), from the Ryukyu Islands to Indonesian waters, Australia, and New Caledonia in the Pacific, and from the Andaman Islands to Madagascar and the Red Sea in the Indian Ocean. The recorded bathymetric depth is from 7 to 70 m. McNeill (1968) recorded the specimens dredged at the depth of 34 – 36 m, with thick Halimeda weed, off North Direction Island in the Great Barrier Reef. Castro (2000) wrote as ʺIt is an inhabitant of coarse-sand sediments (particularly those rich in the coralline alga, Halimeda) that is associated with coral reefs. ʺ The specimen from the Palau Islands was also obtained together with coralline algae. New to the Palau Islands.	en	Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M, Mani, Bhuvaneswari (2023): A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging. Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1): 7-42, DOI: 10.50826/bnmnszool.49.1_7, URL: http://dx.doi.org/10.4103/jpbs.jpbs_1095_23
