This species is distinguished by its large and almost spoon-shaped teeth characteristic of Panaqolus but bifid instead of most generally unicuspid in congeners, and characterized by its specific barcode sequence (JF747003). Differs also from all other congeners except Panaqolus dentex and P. nocturnus by having a uniformly blackish-brown coloration (vs. banded pattern of coloration in P. purusiensis, P. gnomus, P. maccus, and P. changae; or spotted pattern of coloration in P. albomaculatus). It can be separated from Panaqolus dentex by having dark pigment on membrane and branched rays of all fins, as well as a smaller interorbital width (29.4-33.2% HL, mean 31.6, vs. 38.7), a shorter pectoral spine (29.8-31.3% HL, mean 30.3, vs. 34.8) and a greater caudal peduncle depth (12.0-13.4% SL, mean 12.9, vs. 10.8). It is readily distinguished from Panaqolus nocturnus by having larger eye (orbit length 18.8-20.8% HL vs. 13.7-15.9) (Ref. 90183).