Diagnosis: typical extremely elongate, eel-shaped body (maximum body depth 8.7-13.9% of standard length); head length 20.2% SL (Ref. 57129). Head rather rectangular in dorsal outline; snout broadly rounded; eyes more dorsally located; frontal fontanelle intermediate between "knife-shaped" and "sole-shaped"; occipital fontanelle broadly oval-shaped; "dermosphenotic" and supraorbital bones are joined; tooth plates relatively small; premaxillary longer than vomerine (Ref. 248). Distance between occipital process and dorsal-fin base relatively large (8.3-12.4% of standard length); dorsal and anal fins (67.7-75.0% and 50.6-58.9%, respectively, of standard length) very long and sometimes partially confluent with caudal fin (Ref. 57129). Pectoral spine serrated on both sides (Ref. 248, 57129). Gill rakers long and distantly set (Ref. 248).

Coloration: fresh specimens dark brown on back; sides marked with irregular blackish spots, belly light brown to beige; a vertical bar may be present on caudal fin (Ref. 57129). Flanks with vertical rows of small white spots (Ref. 248, 57129).