Similar to Trichomycterus alternatus, T. caudofasciatus, T. longibarbatus, and T. pantherinus, and can be diagnosed from other species of the Trichomycterus by the long filamentous first pectoral-fin ray about 50-70 % of the pectoral-fin length (vs. 0-40 %). Can be distinguised from T. pantherinus by the presence of the anteriormost section of the infraorbital canal (vs. absence) and 8 pectoral-fin rays (vs. 7); from T. alternatus by having 13-14 pleural ribs (vs. 10-12), and by the pelvic-fin insertion placed in a vertical through the centrum of the 17th or 18th vertebra (vs. 14-15th); from T. caudofasciatus by having pelvic-fin insertion, dorsal-fin and anal-fin origin in the vertical through 17th- 18th (vs. 14th-15th), 19th- 21st (vs. 17 th), 23nd- 24 th (vs. 21st- 22nd) respectively; from T. longibarbatus by having shorter nasal barbel, reaching middle of pectoral-fin base (vs. posterior portion of pectoral-fin base), more slender and narrower body (body depth 11.7-13.5 % SL, vs. 14.9-18.2 %, body width 6.4 -8.3 % SL, vs. 8.6- 12.9 %), shorter head (head length 16.8-19.5 % SL (vs. 20.4 - 21.8%). Differs from all congeners from southeastern Brazilian river basins, by having a unique color pattern, consisting of dark pigmentation concentrated along and above midline of flank, but absent below midline (vs. dark pigmentation extending to ventral portion of flank) (Ref. 91059).