taxonID	type	description	language	source
9931BB45ED50628B9D78B1E851C98DC6.taxon	etymology	Etymology. Named after the hill Bukit Anyi at Bukit Sarang, Bintulu, Sarawak, Malaysia, the type locality.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
9931BB45ED50628B9D78B1E851C98DC6.taxon	description	Description. Protoconch. Color: yellow to orange. Sculpture pattern: meshed - rounded to ellipsoidal or undefined mesh shape. Mesh width: 8 - 30 µm. Teleoconch. Color: yellow. First whorl: shouldered, cylindrical. Subsequent whorls: convex to rounded, with a deeply impressed suture. SH: 1.39 - 1.98 mm, SW: 1.32 - 1.72 mm, SI: 1.05 - 1.08. Total number of whorls: 2 1 / 4 - 2 3 / 4. Shell sculpture. Radial sculpture: absent, only weak to strong growth lines are visible. Spiral sculpture: present, strongly sculpted, continuous ribs, more prominent at the periphery. Scales: at the shoulder a continuous spiral row of highly projecting diagonal crown-like scales; subordinate to that, three to four series of tall, broad or acute diagonal scales, regularly spaced, the uppermost of these always stronger than the lower ones, inter-series pacing irregular. Aperture. Shape: oval to rounded. Basal side: rounded, angular at the columellar region. Parietal side: straight. AH: 0.67 - 0.91 mm, AW: 0.90 - 1.17 mm, AI: 0.74 - 0.93. Holotype dimension. SH: 1.91 mm, SW: 1.72 mm, AH: 0.90 mm, AW: 1.14 mm.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
9931BB45ED50628B9D78B1E851C98DC6.taxon	distribution	Distribution. Known from Bukit Anyi and Bukit Lebik, two isolated hills at Bukit Sarang, Bintulu, Sarawak.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
EAF0B755CA06762D7FCE3A73F96B1A67.taxon	etymology	Etymology. Named after the district of Bau, Sarawak, Malaysia, where the type locality Wind Cave Nature Reserve is located.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
EAF0B755CA06762D7FCE3A73F96B1A67.taxon	description	Description. Protoconch. Color: red. Sculpture pattern: meshed - rounded or irregular mesh shape. Mesh width: 12 - 22 µm. Teleoconch. Color: orange to red. First whorl: shouldered, flat both above and below the shoulder. Subsequent whorls: convex shoulder and more rounded at the periphery. SH: 1.16 - 1.62 mm, SW: 1.06 - 1.30 mm, SI: 1.02 - 1.25. Total number of whorls: 2 - 2 1 / 2. Shell sculpture. Radial sculpture: absent, only weak growth lines are visible. Spiral sculpture: present, weakly to strongly sculpted, continuous to discontinuous ribs, more prominent at the periphery. Scales: two to three major spiral series of low and small diagonal scales, regularly spaced, the upper series always stronger than the lower ones, scale series irregularly spaced. Aperture. Shape: rounded and tilted below. Basal side: rounded, angular at the columellar region. Parietal side: straight. AH: 0.57 - 0.78 mm, AW: 0.69 - 0.86 mm, AI: 0.74 - 0.96. Holotype dimension. SH: 1.16 mm, SW: 1.06 mm, AH: 0.58 mm, AW: 0.70 mm.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
EAF0B755CA06762D7FCE3A73F96B1A67.taxon	distribution	Distribution. Known from Gunung Podam and Wind Cave Nature Reserve, Bau, Sarawak.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
CBD13A0CEF642FF4CBF2E543910233F5.taxon	materials_examined	Other material. Lang Cave, Mulu N. P., Mulu, Sarawak (04 ° 01.49 ' N, 114 ° 49.48 ' E): MZU / MOL 17.32, MZU / MOL 17.33, MZU / MOL 17.34, MZU / MOL 17.35. Deer Cave, Mulu N. P., Mulu, Sarawak: JJV 10533 (this sample, approximately 120 individuals, also contains G. muluensis), JJV 10554 (5 individual of G. muluensis, 1 individual G. hadra), JJV 10533 (this sample, approximately 150 individuals, also contains G. muluensis and G. kobelti). Butik = a misspelling of Bukit, a local name for hill.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
CBD13A0CEF642FF4CBF2E543910233F5.taxon	description	Description. Protoconch. Color: orange. Sculpture pattern: meshed - rounded to ellipsoidal or undefined mesh shape. Mesh width: 12 - 24 µm. Teleoconch. Color: orange. First whorl: with a distinct shoulder (provided with a series of minuscule scales), above the shoulder flat and tapering towards the suture, below the shoulder flat and cylindrical. Subsequent whorls: distinctly scalariform, with three separate aspects separated by two or more main spiral series of scales: above the uppermost spiral series gently curved towards the suture; in between both spiral series flat and cylindrical; below the lowest spiral series abruptly narrowed towards the deeply impressed suture (on the final whorl these three aspects fuse, forming a uniformly rounded impression). SH: 2.61 - 2.91 mm, SW: 2.05 - 2.19 mm, SI: 1.21 - 1.37. Total number of whorls: 2 3 / 4 - 3 1 / 4. Shell sculpture. Radial sculpture: absent, but with strong and unevenly layered growth lines. Spiral sculpture: present, weakly sculpted, continuous to discontinuous. Scales: two to four irregularly spaced series of low to high, and minute to broad diagonal scales, densely spaced, the first scale series always the strongest, weaker series appearing later at the spire. Aperture. Shape: rounded, with a tilt below the palatal side. Basal side: rounded, angular at the columellar region. Parietal side: straight to curved. AH: 1.11 - 1.33 mm, AW: 1.32 - 1.48 mm, AI: 0.83 - 1.01.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
CBD13A0CEF642FF4CBF2E543910233F5.taxon	distribution	Distribution. The type locality for G. hadra is Bukit Besungai, Baram, Sarawak. We also obtained it at Mulu, Sarawak. Currently, therefore, the known distribution range is restricted to Mulu and Baram.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
CBD13A0CEF642FF4CBF2E543910233F5.taxon	discussion	Discussion. The paratypes of Thompson and Dance (1983) have a very pale orange color, compared to recently collected materials from Mulu; presumably the color has faded.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
4AC67BAAB23DFD17A5AF66B4DDA82477.taxon	materials_examined	Other material. Jambusan, North Borneo: NHMUK 92.7.20.122, NHMUK 92.7.23.33 - 4. Gunung Liak / Padang, Kampung Skiat Baru, Jambusan, Sarawak (01 ° 24.05 ' N, 110 ° 11.19 ' E): MZU / MOL 16.04, MZU / MOL 16.05, MZU / MOL 16.06, MZU / MOL 16.07. Bukit Siboyuh, Kampung Skiat Baru, Jambusan, Sarawak (01 ° 22.90 ' N, 110 ° 11.69 ' E): MZU / MOL 16.08. Bukit Tongak, Bidi, Bau / Jambusan, Sarawak (01 ° 22.67 ' N, 110 ° 08.32 ' E): MZU / MOL 16.09.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
4AC67BAAB23DFD17A5AF66B4DDA82477.taxon	description	Description. Protoconch. Color: red. Sculpture pattern: smooth. Teleoconch. Color: orange to red. First whorl: rounded or shouldered with flat surfaces above and below the shoulder. Subsequent whorls: convex to rounded; number of whorls: 2 - 2 1 / 4. SH: 1.06 - 1.55 mm, SW: 1.09 - 1.60 mm, SI: 0.94 - 1.12. Shell sculpture. Radial sculpture: absent, only weak growth lines. Spiral sculpture: present, weakly sculpted, continuous ribs, more prominent at the periphery. Scales: two to four series of low and broad vertical scales, regularly spaced, the upper scale series always the strongest, weaker series appear later at the spire, and the spaces between series are irregular. Aperture. Shape: oval. Basal side: rounded, angular at the columellar region. Parietal side: straight, palatal edge attached or removed at the body whorl. AH: 0.60 - 0.95 mm, AW: 0.80 - 1.16 mm, AI: 0.74 - 0.88.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
4AC67BAAB23DFD17A5AF66B4DDA82477.taxon	distribution	Distribution. Known from Gunung Liak / Padang and Bukit Siboyuh at Kampung Skiat Baru, Jambusan, and Bukit Tongak, in the area of Bau, which is close to Jambusan.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
4AC67BAAB23DFD17A5AF66B4DDA82477.taxon	discussion	Discussion. Godwin-Austen (1889), when he described the species, mentioned that the sides of the spire (whorls) are flat, which we find to be the case for the first whorl in our material (as well as in the lectotype). The exact type locality was not specified, but Smith (1893) reported that the specimens of G. hosei described by Godwin-Austen (1889) were from Jambusan, Sarawak. It has to be noted that G. hosei is highly variable in shell shape and sculpture, even within a local population. For example, material we collected at Gunung Liak / Padang have anything between two and four series of broad and low scales. Material from Bukit Tongak has three to four spiral threads with scales. Material from Bukit Siboyuh, finally, is brighter in color (orange), with only one or two spiral series of scales. These three limestone outcrops are all within the area of not more than 10 km radius. Thompson and Dance (1983) noted that G. hosei is widely distributed in Sarawak, and they give Baram, Marudi, Niah, Tatau, and Bukit Sarang as localities. However, as we elaborate in this paper, many of these populations are not conspecific with G. hosei. For example, the image of " G. hosei " provided by Thompson and Dance (1983) - UF 35919, from Batu Gading, Baram, appears conspecific to G. kobelti. Also, their " G. hosei " from Bukit Sarang we here describe as a G. anyiensis sp. n.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
B0798B78B9C62055C2AFD9059605CF99.taxon	etymology	Etymology. Named after the district of Kinabatangan, Sabah, Malaysia, where the type locality Bukit Keruak is located.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
B0798B78B9C62055C2AFD9059605CF99.taxon	description	Description. Protoconch. Color: orange. Sculpture pattern: smooth to meshed - rounded to undefined mesh pattern. Mesh width: 14 - 21 µm. Teleoconch. Color: orange. First whorl: flat and angular at the shoulder. Subsequent whorls: angular, slightly rounded at the periphery, with number of whorls: 2 - 2 1 / 4. SH: 1.00 - 1.32 mm, SW: 1.13 - 1.37 mm, SI: 0.85 - 0.99. Shell sculpture. Radial sculpture: absent, only weak to strong growth lines are visible. Spiral sculpture: present, and strongly sculpted, with continuous to discontinuous ribbings. Scales: two series of diagonal vertical scales, widely spaced in between, both series are strongly sculpted, broad, and the scales are regularly placed. Aperture. Shape: oval. Basal side: rounded, angular at the columellar region. Parietal side: straight, palatal edge attached to the body whorl. AH: 0.54 - 0.66 mm, AW: 0.75 - 0.86 mm, AI: 0.65 - 0.80. Holotype dimension. SH: 1.00 mm, SW: 1.18 mm, AH: 0.54 mm, AW: 0.78 mm.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
B0798B78B9C62055C2AFD9059605CF99.taxon	distribution	Distribution. Known from Bukit Keruak, Batu Tomanggong, and Pangi, in the region of Kinabatangan, Sabah.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
B0798B78B9C62055C2AFD9059605CF99.taxon	discussion	Discussion. Georissa kinabatanganensis is the only species in " scaly group " Georissa to have a flat shell habitus, all examined individuals have a shell that is broader than high.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
97C7B2D5E3E9ECAA887417F70428D806.taxon	materials_examined	Other material. Trade Cave, Niah National Park, Niah, Sarawak (03 ° 49.13 ' N, 113 ° 46.86 ' E): MZU / MOL 17.36. Great Cave, Niah National Park, Niah, Sarawak: MZU / MOL 17.37. Bukit Kaijin, Baram, Sarawak (03 ° 41.75 ' N, 114 ° 27.55 ' E): MZU / MOL 17.38, MZU / MOL 17.39, MZU / MOL 17.40, MZU / MOL 17.41, MZU / MOL 17.42, MZU / MOL 17.43, MZU / MOL 17.44, MZU / MOL 17.45, MZU / MOL 17.46, MZU / MOL 17.47, MZU / MOL 17.48, MZU / MOL 17.49, JJV 10217. Bukit Kasut, Niah N. P., Niah, Sarawak: JJV 10254. Niah N. P., Niah, Sarawak: JJV 1565, JJV 5466, JJV 10306, JJV 10392. Deer Cave, Mulu N. P., Mulu, Sarawak: JJV 10533 (the sample, approximately 150 individuals, also contains G. muluensis and G. hadra). Tatau river valley, Bukit Sarang, Bintulu, Sarawak: JJV 12551, JJV 12838. From Thompson and Dance 1983, Niah, Baram (Sarawak, Borneo): UF 35919, UF 36179 (not seen).	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
97C7B2D5E3E9ECAA887417F70428D806.taxon	description	Description. Protoconch. Color: orange to red. Sculpture: meshed - semi-oval mesh shape. Mesh width: 11 - 22 µm. Teleoconch. Color: ranging from red to yellow. First whorl: convex to rounded. Subsequent whorls: convex to rounded. SH: 1.75 - 2.11 mm, SW: 1.48 - 1.75 mm, SI: 1.18 - 1.28. Total number of whorls: 2 3 / 4 - 3. Shell sculpture. Radial sculpture: absent, only weak growth lines. Spiral sculpture: present with thin but strongly continuous spiral ribs, forming small acute scales near the suture. Scales: three to four spiral rows of tilted, nearly vertical scales, the upper series stronger than the lower ones, scale prominence ranging from high to low and from small and acute to broadly sculpted and ear-like. Scales are regularly spaced, as are the scale series themselves. Aperture. Shape: rounded to oval. Basal side: rounded, angular before the columellar region. Parietal side: curved. AH: 0.82 - 1.04 mm, AW: 1.02 - 1.17 mm, AI: 0.71 - 0.90.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
97C7B2D5E3E9ECAA887417F70428D806.taxon	distribution	Distribution. The lectotype in Senckenberg (SMF 215893 a) was obtained from an unspecified location. As far as known, the species is restricted to the area of Niah to Baram, northern Sarawak. Thompson and Dance (1983) also stated that they examined this species from Beluru, which is located between Niah and Baram.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
79A2CF435F54680FFC2B699CC1416DE5.taxon	materials_examined	Other material. Deer Cave, Mulu National Park, Mulu, Sarawak: JJV 10533 (this sample, approximately 120 individuals, also contains specimens of G. hadra), JJV 10554 (this sample contains 5 individual of G. muluensis, 1 individual G. hadra), JJV 10533 (this sample, approximately 150 individuals, also contains specimens of G. hadra and G. kobelti). Mulu N. P., Mulu, Sarawak: JJV 10527.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
79A2CF435F54680FFC2B699CC1416DE5.taxon	etymology	Etymology. Named after Mulu National Park, Sarawak, Malaysia, the type locality.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
79A2CF435F54680FFC2B699CC1416DE5.taxon	description	Description. Protoconch. Color: yellow. Sculpture pattern: meshed - ellipsoidal mesh shape. Mesh width: 16 - 26 µm. Teleoconch. Color: yellow. First whorl: shouldered, above the shoulder flat, nearly horizontal; below the shoulder flat, cylindrical, but abruptly withdrawn into the deeply incised suture. Subsequent whorls: convex to rounded. SH: 1.67 - 2.05 mm, SW: 1.57 - 1.79 mm, SI: 1.08 - 1.18. Total number of whorls: 2 1 / 4 - 3. Shell sculpture. Radial sculpture: absent, only weak to strong growth lines are visible. Spiral sculpture: present, consisting of thin, but strongly sculpted and continuous ribs. Scales: two to three series of tall and diagonal scales, regularly spaced, the upper scale series always stronger than the lower ones, weaker series appear later at the spire or consist only of randomly spaced arrays of acute nodules, widely spaced between the first and second scale series, more densely spaced later. Aperture. Shape: rounded to slightly oval. Basal side: rounded, angular at the columellar region. Parietal side: straight to slightly curved. AH: 0.82 - 0.98 mm, AW: 1.03 - 1.18 mm, AI: 0.77 - 0.83. Holotype dimension. SH: 1.67 mm, SW: 1.53 mm, AH: 0.82 mm, AW: 1.07 mm.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
79A2CF435F54680FFC2B699CC1416DE5.taxon	distribution	Distribution. Known only from the small area of Lagang Cave, Mulu National Park, Mulu, Sarawak, Malaysia.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
2CCB43F09EFE1504D8BC30CEE486ACF4.taxon	materials_examined	Other material. Painted Cave, Niah National Park, Niah, Sarawak (03 ° 48.68 ' N, 113 ° 47.25 ' E): MZU / MOL 17.25.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
2CCB43F09EFE1504D8BC30CEE486ACF4.taxon	description	Description. Protoconch. Color: red. Sculpture pattern: smooth and meshed - ellipsoid to irregular mesh shape. Mesh width: 12 - 19 µm. Teleoconch. Color: orange to red. First whorl: curved above the shoulder, flat and cylindrical below the shoulder. Subsequent whorls: convex, angular at the periphery. SH: 1.81 - 2.53 mm, SW: 1.51 - 1.99 mm, SI: 1.10 - 1.29. Total number of whorls: 3 - 3 1 / 4. Shell sculpture. Radial sculpture: absent, only strong and unevenly layered growth lines. Spiral sculpture: present, strongly sculpted, continuous to discontinuous, well defined from the first whorl all the way to the peristome. Scales: a single spiral series of low and minute acute scales, regularly spaced at the first whorl, but weaker, grading to imperceptible on the body whorl. Aperture. Shape: rounded. Basal side: rounded, angular at the columellar region. Parietal side: straight to curved. AH: 0.85 - 1.24 mm, AW: 0.92 - 1.27 mm, AI: 0.83 - 1.02.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
2CCB43F09EFE1504D8BC30CEE486ACF4.taxon	distribution	Distribution. Known to occur only at Niah, Sarawak.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
2CCB43F09EFE1504D8BC30CEE486ACF4.taxon	discussion	Discussion. Both Godwin-Austen (1889) and Thompson and Dance (1983) did not mention anything about the small scale-like nodules close to the suture of G. niahensis. Godwin-Austen (1889): " Shell elongately conoid, solid, imperforate; sculpture a very in-distinct, ill-defined spiral liration, about 20 on the penultimate whorl, upon a rough surface crossed by transverse lines of growth; color ruddy ochre; spire high; apex pointed, finely papillated, minutely lirate; suture impressed; whorls 4 1 / 2 convex; aperture oval, oblique; peristome simple, acute below; columellar margin straight ". Thompson and Dance (1983): " G. niahensis is similar in sculpture to G. williamsi but is much larger. G. niahensis also shows similarities to the hosei group in the depth of the suture and the relatively rapid expanding whorls, but it lacks the node-like sculpture found among species of that group. " The scales are relatively small which are not very conspicuous among the strong growth lines, and this is the reason why in the previous description of the species the scale characters were lacking. Thompson and Dance (1983) compared G. niahensis with what they call the hosei group, based on the size and the deeply impressed suture.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
0489A22D9C569A311C9436A606D45126.taxon	materials_examined	Other materials. Gunong Silabur, Serian, Sarawak, Malaysia (00 ° 57.45 ' N, 110 ° 30.20 ' E): MZU / MOL 17.09, MZU / MOL 17.10, MZU / MOL 17.11, MZU / MOL 17.12, MZU / MOL 17.13, MZU / MOL 17.14, MZU / MOL 17.15, MZU / MOL 17.16, MZU / MOL 17.17, MZU / MOL 17.18, MZU / MOL 17.19, MZU / MOL 17.20, MZU / MOL 17.21, MZU / MOL 17.22, MZU / MOL 17.23, MZU / MOL 17.24.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
0489A22D9C569A311C9436A606D45126.taxon	description	Description. Protoconch. Color: red to brown. Sculpture pattern: smooth to meshed, with ellipsoid mesh shape. Mesh width: 11 - 26 µm. Teleoconch. Color: brown to red. First whorl: shouldered, slightly curved above the shoulder, flat, cylindrical below the shoulder. Subsequent whorls: initially shouldered, but soon grading into uniformly rounded and quickly expanding whorls, with a deeply impressed suture; number of whorls: 2 1 / 4 - 2 1 / 2. SH: 1.16 - 1.31 mm, SW: 1.12 - 1.20 mm, SI: 1.03 - 1.09. Shell sculpture. Radial sculpture: absent, only weak to strong growth lines are visible. Spiral sculpture: present, strong spiral sculpture. Scales: a single series of low, small and acute, unevenly spaced scales above the periphery, occasionally, in the vicinity of the aperture, subordinate series of minute scales accompany the major series. Aperture. Shape: rounded, tilted below the palatal side. Basal side: rounded, strongly angular at the columellar region. Parietal side: straight, palatal edge attached to the body whorl. AH: 0.58 - 0.63 mm, AW: 0.75 - 0.85 mm, AI: 0.73 - 0.81.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
0489A22D9C569A311C9436A606D45126.taxon	distribution	Distribution. Only known from the type locality, Gunung Silabur, Serian, Sarawak, Malaysia.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
0489A22D9C569A311C9436A606D45126.taxon	discussion	Discussion. In the original description, Thompson and Dance (1983) did not compare G. pyrrhoderma with members of their hosei - group (which our molecular analyses show it belongs in). Instead, they considered it allied to G. borneensis. Possibly this misalignment was caused by the fact that the type specimens appear to lack the series of scales that is present on most of the specimens we collected. Nonetheless, given the restricted range of collection localities at Gunung Silabur and the degree of variability in our material, we consider our and Thompson and Dance's material as conspecific. The paratypes specimen NHMUK 1984005 (Semabang entrance to Lobang Batu Cave, W. side of Gunong Selabor, 1 st. Div., Sarawak, Malaysia: seen) is G. silaburensis.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
9CC8A70C3E74AC89FAF5733EB3AC0C22.taxon	materials_examined	Other material. Simbaluyon limestone hill, Sabah, Malaysia: RMNH / MOL 333913, RMNH / MOL 333919. Crocker Range National Park, Gua Laing, Keningau, Sabah (05 ° 29.00 ' N, 116 ° 08.00 ' E): RMNH / MOL 335180, ZMA / MOLL 315592, ZMA / MOLL 315593, JJV 1119. Sepulut Valley, Gua Pungiton, Sabah (04 ° 42.41 ' N, 116 ° 36.04 ' E): BOR / MOL 28, BOR / MOL 12770, JJV 7544. Sepulut valley, Gua Sanaron, Sabah (04 ° 42.05 ' N, 116 ° 36.01 ' E): BOR / MOL 29, BOR / MOL 32, BOR / MOL 3493, JJV 7660. Pinangah valley, Batu Urun (Bukit Sinobang), Sabah (04 ° 48.40 ' N, 116 ° 37.35 ' E): BOR / MOL 31, JJV 1144, JJV 5632, JJV 7993. Mahua, Sabah: BOR / MOL 33. Pun Batu, Sepulut, Sabah (04 ° 45.00 ' N, 116 ° 10.00 ' E): JJV 1268. Sepulut valley, Batu Punggul, Sabah: JJV 1904.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
9CC8A70C3E74AC89FAF5733EB3AC0C22.taxon	description	Description. Protoconch. Color: red to brown. Sculpture: meshed - ellipsoidal mesh pattern. Mesh width: 29 - 54 µm. Teleoconch. Color: brown to red. First whorl: convex to rounded. Subsequent whorls: convex to rounded. SH: 1.32 - 1.86 mm, SW: 1.14 - 1.48 mm, SI: 1.12 - 1.26. Total number of whorls: 2 1 / 2 - 3 1 / 4. Shell sculpture. Radial sculpture: often present, when formed by vertical connections between corresponding scales on successive spiral ribs. These vertical connections, especially on the first whorls, form evenly spaced ribs that are raised when crossing a spiral rib. Spiral sculpture: present at the early teleoconch, subsequently becoming weaker, and later only short discontinuous lines are visible in between the radial sculptures. Scales: usually three or four discontinuous series of vertical, low to high-projecting scales, broad to pointed (only if the spiral series of scales are discontinuous). Aperture. Shape: rounded to slightly oval. Basal side: rounded, slightly angular before the columellar region. Parietal side: straight, connected to the palatal edge. AH: 0.58 - 0.83 mm, AW: 0.70 - 0.94 mm, AI: 0.76 - 0.92. Holotype dimension. SH: 1.60 mm, SW: 1.28 mm, AH: 0.66 mm, AW: 0.80 mm.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
9CC8A70C3E74AC89FAF5733EB3AC0C22.taxon	distribution	Distribution. The type locality of Georissa saulae is Laying cave, in the Crocker Range, Keningau, Sabah (a misspelling of Laing cave). Otherwise known from limestone outcrops in Sabah's interior, viz., Simbaluyon, Sinobang, Sanaron, and Pungiton, and also has been recorded from Mahua, Sabah, which is not a limestone area. Phung et al. (2017) also report it from Pulau Tiga, Sabah.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
9CC8A70C3E74AC89FAF5733EB3AC0C22.taxon	discussion	Discussion. Georissa saulae was initially described as Hydrocena saulae van Benthem-Jutting, 1966, then assigned to the genus Georissa by Thompson and Dance (1983). Thompson and Dance (1983) compared G. saulae with G. scalinella, and even suggested G. saulae might be a subspecies. In contrast, we find that G. saulae is a proper species with very distinct conchological characters, especially the presence of radial ribs on the shell, which makes it easy to identify. In some specimens from the entrance of the Batu Sanaron cave system, the vertical scales are spaced, and radial sculpture is weak. Such individuals presumably represent the hybrid zone with the cave-dwelling G. filiasaulae (Haase and Schilthuizen 2007, Schilthuizen et al. 2012).	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
52CEE790316365EEBF506FD11C98E6C7.taxon	description	Description. Protoconch. Color: orange to red. Sculpture: smooth to meshed - semi oval mesh to undefined mesh pattern. Mesh width: 7 - 17 µm. Teleoconch. Color: orange. First whorl: flat at the shoulder. Subsequent whorls: flat above, slightly rounded below the periphery. Total number of whorls: 2 1 / 4 - 2 1 / 2. SH: 1.56 - 1.80 mm, SW: 1.46 - 1.65 mm, SI: 1.03 - 1.15. Shell sculpture. Radial sculpture: absent, only weak to strong growth lines are visible. Spiral sculpture: present, and strongly sculpted, with continuous and discontinuous ribbing. Scales: a series of acute scales, low to highly projected, and regularly spaced. Intercept between growth lines and spiral ribbings form small pointed scale structures throughout the length of the body whorl. Aperture. Shape: oval. Basal side: rounded, angular at the columellar region. Parietal side: straight, palatal edge attached to the body whorl. AH: 0.78 - 0.94 mm, AW: 0.97 - 1.12 mm, AI: 0.75 - 0.89. Holotype dimension. SH: 1.88 mm, SW: 1.72 mm, AH: 0.84 mm, AW: 1.18 mm.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
52CEE790316365EEBF506FD11C98E6C7.taxon	distribution	Distribution. Known only from the type locality, Teck Guan Estate, Lahad Datu, Sabah, and also reported by Phung et al. (2017) at Pulau Tiga, Sandakan, Sabah. However, this may also refer to one of the other " scaly group " species from Sabah.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
52CEE790316365EEBF506FD11C98E6C7.taxon	discussion	Discussion. Georissa scalinella was first described as Hydrocena scalinella van Benthem-Jutting, 1966, before reclassified as Georissa by Thompson and Dance (1983). van Benthem-Jutting (1966) described G. scalinella as having strong spiral ribbing and multiple lines of scales.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
834CC209F159637B68AE4B55D7F350E1.taxon	etymology	Etymology. Named after the town of Sepulut, Sabah, Malaysia, near which the type locality Gua Pungiton, as well as the other known localities, is located.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
834CC209F159637B68AE4B55D7F350E1.taxon	description	Description. Protoconch. Color: red to brown. Sculpture: smooth to meshed - semi-oval mesh to undefined mesh pattern. Mesh width: 7 - 17 µm. Teleoconch. Color: red. First whorl: flat to rounded at the shoulder. Body whorl: rounded, with number of whorls: 2 - 2 3 / 4. SH: 1.11 - 1.52 mm, SW: 1.11 - 1.37 mm, SI: 0.94 - 1.07. Shell sculpture. Radial sculpture: absent, only weak growth lines are visible. Spiral sculpture: present, and strongly sculpted. Scales: a series of pointed vertical scales, acute and highly projected, and regularly spaced. Aperture. Shape: oval and tilted below. Basal side: rounded, angular at the columellar region. Parietal side: straight, palatal edge attached to the body whorl. AH: 0.62 - 0.81 mm, AW: 0.76 - 0.96 mm, AI: 0.72 - 0.87. Holotype dimension. SH: 1.34 mm, SW: 1.23 mm, AH: 0.65 mm, AW: 0.82 mm.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
834CC209F159637B68AE4B55D7F350E1.taxon	distribution	Distribution. Distributed in the Sepulut Valley, Sabah; known from the following limestone localities: Simbaluyon, Sanaron, Tinahas, and Pungiton.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
834CC209F159637B68AE4B55D7F350E1.taxon	discussion	Discussion. Georissa sepulutensis and G. kinabatanganensis were previously included in G. scalinella (van Benthem-Jutting, 1966). Based on the genetic and morphological distinctness, we here consider them as separate species.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
4E30116CE956D1EBCE91DC54A80C25EE.taxon	etymology	Etymology. Named after Gunung Silabur, Serian, Sarawak, Malaysia, the type locality.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
4E30116CE956D1EBCE91DC54A80C25EE.taxon	description	Description. Protoconch. Color: red. Sculpture pattern: meshed - round to irregular mesh pattern. Mesh width: 8 - 18 µm. Teleoconch. Color: red. First whorl: rounded. Subsequent whorls: convex, number of whorls: 2 - 2 1 / 4. SH: 1.59 - 1.99 mm, SW: 1.50 - 1.76 mm, SI: 1.06 - 1.13. Shell sculpture. Radial sculpture: absent or weak to strong growth lines. Spiral sculpture: present, thin but strongly sculpted, continuous ribs, more prominent at the periphery. Scales: two to six or more randomly sculpted series of low and broad horizontal scales, or else acute horizontal nodules on the spiral sculpture, scale series irregularly spaced, which series is the most prominent is not consistent across individuals. Aperture. Shape: rounded. Basal side: rounded, angular at the columellar region. Parietal side: straight, palatal edge attached to slightly removed from the body whorl. AH: 0.95 - 1.09 mm, AW: 1.00 - 1.17 mm, AI: 0.92 - 0.99. Holotype dimension. SH: 1.68 mm, SW: 1.53 mm, AH: 0.95 mm, AW: 1.09 mm.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
4E30116CE956D1EBCE91DC54A80C25EE.taxon	distribution	Distribution. Known from the inside of the cave system of Gunung Silabur, Serian, Sarawak.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
4E30116CE956D1EBCE91DC54A80C25EE.taxon	discussion	Discussion. Georissa silaburensis was only found inside the cave entrance, with water flowing from the cave roof, and approximately less than 50 % light penetration. In shell shape and reduced sculpture, it resembles another cave specialist, G. filiasaulae.	en	Khalik, Mohd Zacaery, Hendriks, Kasper, Vermeulen, Jaap J., Schilthuizen, Menno (2018): A molecular and conchological dissection of the " scaly " Georissa of Malaysian Borneo (Gastropoda, Neritimorpha, Hydrocenidae). ZooKeys 773: 1-55, DOI: http://dx.doi.org/10.3897/zookeys.773.24878, URL: http://dx.doi.org/10.3897/zookeys.773.24878
