New species of the eel genera Dysomma and Dysommina from Vietnam, South China Sea (Anguilliformes: Synaphobranchidae)

Abstract

AbstractTwo new cutthroat eel species are described from Vietnam. Dysomma intermedium sp. nov. has a relatively long trunk, being about half of head length and anal‐fin origin more than twice pectoral‐fin length behind the pectoral‐fin tip; pectoral fin well developed; dorsal‐fin origin over or slightly in front of base of pectoral fin; two intermaxillary teeth; four or five compound teeth on ethmovomer; single row of seven or eight teeth on lower jaw; total lateral‐line pores 70–76; and 21 pre‐anal and 118–124 total vertebrae. Dysommina brevis sp. nov. differs from congeners by having a trunk shorter than head length, its length 11.1%–11.8% TL; a short pre‐anal length 24.6%–25.6% TL, eye diameter 11.8%–12.3% head length; three large and one or two small teeth on ethmovomer; and fewer teeth on the upper and lower jaws. In addition, a specimen representing the first record of Dysommina orientalis in Vietnamese water is documented.