Diagnosed from all other species in the Trichomycteridae by the deep posterior region of the body, including the caudal peduncle and caudal fin (caudal-peduncle depth 22.8-25.4% SL in adults). Distinguished also from all members of the genus Trichomycterus by the shape of the caudal fin in adults, in which the fin is prolonged into long, markedly diverging and somewhat irregular lobes forming a concave posterior margin (vs. caudal fin either truncate, emarginate, or round). In addition, it can be separated from all other congeners and possibly all other trichomycterids by pronounced elongation of the neural and hemal spines of the caudal vertebrae along the mid-portion of the caudal peduncle. Differs further from all other trichomycterids, except Trichomycterus stawiarski, by having thick-ossified and rigid procurrent caudal-fin rays, markedly distinct from the flexible and splint-like procurrent rays in other trichomycterids. The coloration pattern consists of closely set large irregular blotches overlain by a more superficial layer of small round markings, which distinguishes this species from the majority of other species currently in Trichomycterus, except Trichomycterus stawiarski. Additional characters useful for recognizing this species which could not be checked in all species of Trichomycteridae include urohyal foramen reduced to a slender canal and lateral line with 5-7 pores (Ref. 75785).

Description: Dorsal fin iv,8; Anal fin iv,6; Pectoral fin i+7; Pelvic fin i+4 rays (Ref. 75785).