Accepted by L. Page: 31 Dec. 2006; published: 12 Feb. 2007 25 ZOOTAXA ISSN 1175-5326 (print edition) ISSN 1175-5334 (online edition) Copyright © 2007 · Magnolia Press Zootaxa 1406: 25–32 (2007) www.mapress.com/ zootaxa/ Pseudecheneis maurus, a new species of glyptosternine catfish (Teleostei: Sisoridae) from Central Vietnam HEOK HEE NG 1 & HEOK HUI TAN 2 1 Fish Division, Museum of Zoology, University of Michigan, 1109 Geddes Avenue, Ann Arbor, Michigan 48109-1079, USA. E-mail: heokheen@umich.edu Current address: Raffles Museum of Biodiversity Research, Department of Biological Sciences, National University of Singapore, 6 Science Drive 2, Singapore 117600. 2 Raffles Museum of Biodiversity Research, Department of Biological Sciences, National University of Singapore, 6 Science Drive 2, Singapore 117600. E-mail: dbsthh@nus.edu.sg Abstract A new species of sisorid catfish, Pseudecheneis maurus, is described from the Song Thuy Loan drainage in Central Viet- nam. Pseudecheneis maurus can be distinguished from congeners in having a combination of a very short adipose-fin base (1.2 times length of anal-fin base vs. 1.5–2.0 times; 15.7% SL vs. 17.6–30.6), thoracic adhesive apparatus with sul- cae not meeting at midline and the absence of distinct pale spots on the body. Key words: Annam Cordillera, Southeast Asia, Glyptosterninae Introduction Sisorid catfishes of the genus Pseudecheneis Blyth, 1860, are diagnosed by a thoracic adhesive apparatus con- sisting of a series of transverse ridges (laminae) separated by grooves (sulcae) (de Pinna, 1996; Roberts, 1998), and are found in the upper reaches of rivers throughout the Subhimalayan and Indochinese region. Recent studies (Ng & Edds, 2005; Ng, 2006a; Ng, 2006b) recognize eleven valid species of Pseudecheneis: P. sulcata (M'Clelland, 1842); P. paviei Vaillant, 1904; P. tchangi (Hora, 1937); P. immaculata Chu, 1982; P. sul- catoides Zhou & Chu, 1992; P. sympelvica Roberts, 1998; P. crassicauda Ng & Edds, 2005; P. serracula Ng & Edds, 2005; P. eddsi Ng, 2006; P. stenura Ng, 2006; and P. suppaetula Ng, 2006. The ichthyofauna of the short coastal drainages that drain the eastern face of the Annam Cordillera in Central Vietnam has not been explored until recently, where it has been found to contain a considerable number of endemic species (e.g. Freyhof & Serov, 2001; Ng & Freyhof, 2005). During a recent ichthyological survey of one such drainage in Central Vietnam carried out by HHT, a specimen of Pseudecheneis was obtained from a region where the genus had not been previously reported. This specimen is here shown to belong to an unde- scribed species, which is described below as Pseudecheneis maurus, sp. nov. Material and methods Measurements were made point to point with dial calipers, and data recorded to tenths of a millimeter. Counts and measurements were made on the left side of specimens. Subunits of the head are presented as proportions of head length (HL). Head length and measurements of body parts are given as proportions of standard length (SL). Measurements follow those of Ng & Rainboth (2001). Material examined in this study is deposited in the following institutions: Academia Sinica, Institute of