Exostoma dulongensis a new glyptosternine catfish from the Irrawaddy basin Yunnan, China (Siluriformes: Sisoridae) Author Luo, Zhaojun Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, Nay Pyi Taw 05282, Myanmar & Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, China https: // orcid. org / 0000 - 0002 - 0924 - 5560 Author Chen, Xiaoyong Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, Nay Pyi Taw 05282, Myanmar text Zootaxa 2020 2020-06-22 4802 1 99 110 journal article 10.11646/zootaxa.4802.1.6 1175-5326 3904910 93D343D6-CA14-450F-AF95-3FCAFA0A6313 Key to Exostoma species 1 Adipose fin confluent with caudal fin..................................................................... 2 – Adipose fin separated from caudal fin..................................................................... 9 2 Pelvic fin reaching anus................................................................................ 3 – Pelvic fin not reaching anus............................................................................. 8 3 Parallel or rounded striae on anterolateral surface of lips...................................................... 4 – Parallel and rounded striae on anterolateral surface of lips........................................ E. gaoligongense 4 Parallel striae on anterolateral surface of lips................................................................ 5 – Rounded striae on anterolateral surface of lips............................................................... 6 5 Total vertebrae 42–43, caudal fin weakly forked..................................................... E. ericinum – Total vertebrae 39–41, caudal fin weakly emarginate................................................ E. chaudhurii 6 Outer mandibular barbel reaching or surpassing first pectoral fin base................................. E. vinciguerrae – Outer mandibular barbel reaching 2/3 of distance between its base of first pectoral fin ray............................ 7 7 Caudal fin weakly forked, caudal peduncle 9.2%–9.7% SL........................................... E. berdmorei – Caudal fin lunate, caudal peduncle 6.2%–8.5% SL................................................ E. peregrinator 8 Total vertebrae 40–43, caudal fin weakly forked, dorsal fin base length 6.4%–10.6% SL........... E. dulongensis sp. nov. – Total vertebrae 38–39, caudal fin lunate, dorsal fin base length 12.4%–13.5% SL.......................... E. sawmteai 9 Posterior tip of adipose without incision.................................................................. 10 – Posterior tip of adipose with incision..................................................................... 16 10 Pelvic fin reaching anus............................................................................... 11 – Pelvic fin not reaching anus............................................................................ 14 11 Parallel or rounded striae on anterolateral surface of lips......................................................12 – Parallel and rounded striae on anterolateral surface of lips............................................... E. kottelati 12 Rounded striae on anterolateral surface of lips.............................................................. 13 – Parallel striae on anterolateral surface of lips.................................................... E. tenuicaudata 13 11 branched pectoral fin rays, head length 22.6%–24.9% SL, head width 79.7%–88.2% HL........... E. mangdechhuensis – 12–13 branched pectoral fin rays, head length 21.4% SL, head width 97.9% HL............................ E. labiatum 14 Dorsal profile slightly arched, post-dorsal profile gently sloping............................................... 15 – Dorsal profile greatly arched, post-dorsal profile severely sloping......................................... E. stuarti 15 Caudal fin lunate, depth at anus 10.4%–12.3% SL, caudal peduncle depth 6.7%–8.6% SL, caudal peduncle length 9.5%–11.1% SL.......................................................................................... E. tibetana – Caudal fin emarginate, depth at anus 14.0%–16.5% SL, caudal peduncle depth 33.0%–43.0% SL, caudal peduncle length 44.0%–57.0% SL.......................................................................... .. E. barakensis 16 Nasal barbel reaching beyond posterior orbital margin, 19.0%–31.0% HL, caudal peduncle length 17.0%–20.5% SL..................................................................................................... E. sectile – Nasal barbel not reaching posterior orbital margin, 34.0%–43.0% HL, caudal peduncle length 26.3%–28.0% SL....................................................................................................... E. effrenum