Abstract:
Two 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.