Biodiversity assessment in the Lower Mekong basin: First record of the genus Oncosclera (Porifera: Spongillina: Potamolepidae) from the Oriental Region Author Manconi, Renata Department of Science for Nature and Environmental Resources, Sassari University, Sassari, 07100 Italy. E-mail: r. manconi @ uniss. it Department of Biology, Faculty of Science, Khon Kaen University, Khon Kaen, 40002 Thailand. E-mail: tongkku @ windowslive. com Applied Taxonomic Research Center, Faculty of Science, Khon Kaen University, Khon Kaen, 40002 Thailand. Author Ruengsawang, Nisit Author Ledda, Fabio D. Department of Science for Nature and Environmental Resources, Sassari University, Sassari, 07100 Italy. E-mail: r. manconi @ uniss. it Department of Biology, Faculty of Science, Khon Kaen University, Khon Kaen, 40002 Thailand. E-mail: tongkku @ windowslive. com Applied Taxonomic Research Center, Faculty of Science, Khon Kaen University, Khon Kaen, 40002 Thailand. Author Hanjavanit, Chutima Author Sangpradub, Narumon text Zootaxa 2012 2012-11-08 3544 41 51 journal article 1175-5326 561BB012-CAAA-43F8-BFF7-587155EAE442 Oncosclera asiatica Manconi & Ruengsawang , sp. nov. Figures 1–4 ; Table 1 Materials. Holotype MSNG 56534 a, Ban Huai Sai (16˚46ʹ20.40˝N, 102˚42ʹ48.22˝E) type locality, Pong River , Thailand , 14.vi.2008 , encrusting on submerged bamboo stick in contact with the paratype , leg. Nisit Ruengsawang (schizotype DTRG FW719 ) . Paratype MSNG 56534 b, associated with the holotype on submerged bamboo stick ( Fig. 2 , arrow), Ban Huai Sai (16˚46ʹ20.40˝N, 102˚42ʹ48.22˝E), Pong River , Thailand , 14.vi.2008 , leg. Nisit Ruengsawang. Topotype OS DP2 , Ban Huai Sai (16˚46ʹ20.40˝N, 102˚42ʹ48.22˝E), type locality, Pong River , Thailand , 20.viii.2010 , leg. Nisit Ruengsawang , 1 specimen on PVC net. Comparative materials. O. jewelli , Rio Tainhas, São Francisco de Paula, Rio Grande do Sul , 10.ix.1960 , C. Volkmer-Ribeiro det. ( Holotype MNRJ 001, schizotype DTRG FW 547); O. jewelli , Rio Tainhas, São Francisco de Paula, Rio Grande do Sul , Brazil , C. Volkmer leg. det., 17.i.1971 (topotype BMNH 1978.12.12.12, ex-FZBRS 124, schizotype DTRG FW 410); O. jewelli , FZBRS MCN 1080 , River Teinhesves, 11.i.1983 (fragment FW 487); O. macrospiculata Niger, Timbuktu, on shells of Aetheria sp., 1931 , A. Chevalier leg., Topsent det. ( MNHN DT 2846, fragment DTRG FW 508ab); O. rousseletii, Zambezi River above Victoria Falls ( holotype BMNH 06.2.28.IC, 13. IIIC , alcohol, schizotype DTRG FW 390); O. schubotzi , Aruwimi River near Banalia, on Aetheria elliptica , v.1908 , Schubotz leg., Weltner 1919 det. ( holotype ZMB 3716a, schizotype DTRG FW 539); O . schubotzi , Aruwimi River near Banalia, v.1908 , Schubotz leg., Weltner 1919 det. ( paratype MRAC 205 ex-ZMB 3716, dry, schizotype DTRG FW 471); O . gilsoni , River Waidina , Viti Levu, Fiji Islands , E. Topsent det., 22.x.1897 (Type IRScNB POR.048, schizotype DTRG FW 361).