Trypauchen Valenciennes in Cuvier & Valenciennes

Edward O. Murdy, 2006, A revision of the gobiid fish genus Trypauchen (Gobiidae: Amblyopinae)., Zootaxa 1343, pp. 55-68 : 55-56

[[ Trypauchen Valenciennes in Cuvier & Valenciennes ]]

Introduction

Gobius vagina was described by Bloch and Schneider (1801) from a single specimen collected in Tranquebar, India. The original description was brief, but stated that an ovalshaped opening was present on the dorsal edge of the operculum. Because of this unusual, pouch-like structure at the dorsal margin of the operculum, Valenciennes in Cuvier and Valenciennes (1837) erected the genus Trypauchen [from the Greek trypa (hole) and auchen (neck)] for Gobius vagina . The function of the opercular pouch is not known, but this structure is only found in the following genera of Amblyopinae: Amblyotrypauchen , Ctenotrypauchen , Trypauchen , and Trypauchenichthys .

Trypauchen vagina is locally abundant in certain regions and is even used as a food source (Rainboth, 1996), but it has been little studied. However, records and brief descriptions of T. vagina are numerous: India (Day, 1878; Hora, 1924); Thailand (Fowler, 1935; H.M. Smith, 1945); Singapore (Larson and Lim, 2005); Mekong River (Rainboth, 1996); various parts of Indonesia (Bleeker, 1860; Kottelat et al., 1993); China (Richardson, 1844; Günther, 1861; Rendahl, 1924; Herre, 1927); and Taiwan (Chen and Fang, 1999).

In addition to T. vagina , four other species were described and assigned to Trypauchen : T. microcephalus Bleeker, 1860 ; T. raha Popta, 1922 ; T. taenia Koumans, 1953 ; and T. wakae Jordan & Snyder, 1901 . All were described from Indonesian specimens, except for T. wakae , which was described from Japan.

In his major work on the gobioid fishes of the Indo-Australian Archipelago, Koumans (1953) provided the only systematic review of Trypauchen to date. Koumans (1953) included T. raha , T. taenia , and T. vagina in his treatment of Trypauchen . Trypauchen wakae was likely excluded because it was only known from Japan and T. microcephalus was placed in Ctenotrypauchen by Koumans. Koumans (1953) separated the three species of Trypauchen by numbers of longitudinal and transverse scale rows. However, based on examination of the types and/or images of the types, differences in pelvic fin structure, scalation, and osteology between T. vagina and its putative congeners are evident. Consequently, I propose herein a new diagnosis for Trypauchen and that Trypauchen comprises only two species: T. vagina and an undescribed species from Myanmar, Malaysia, Thailand, Vietnam, and China.