Additional records of the snake eel Ophichthus aphotistos (Anguilliformes: Ophichthidae) from Japan and Taiwan

Abstract

A single Japanese (469 mm total length) and two Taiwanese (469 and 657 mm total length) specimens of the snake eel Ophichthus aphotistos McCosker and Chen, 2000, collected from off Yaku-shima island (East China Sea) and northeastern Taiwan, were newly identified in museum collections. Because known morphological characteristics of the species were based solely on three type specimens, descriptions of the present three additional specimens are provided. The present three specimens differ from the holotype and one of two paratypes of O. aphotistos in the arrangement of jaw teeth (biserial anteriorly and uniserial posteriorly vs. biserial), although such can be regarded as an intraspecific variation, remaining paratype having the same tooth-pattern as the newlyfound specimens. Ophichthus aphotistos is characterized by the following combination of characters: head 7.6–8.5% TL; tail 59–62% TL; body depth at gill opening 2.0–2.9% TL; dorsal fin originating well behind posterior margin of pectoral fin, distance from the origin to the margin almost equal to one pectoral-fin length; pectoral fin rounded, not enlarged distinctly; preoperculomandibular pores 6+2; teeth on maxilla and vomer biserial anteriorly; body uniformly brown, without markings; total vertebrae 157–162 and mean vertebral formula (MVF) 18-59-160. The new Japanese standard name, “Yoiyamiumihebi”, is proposed for the species.