Trichomycterus minus Fernández & Vari 2012

Diagnosed from other species of Trichomycterus, except T. alterus, T. aguarague, T.belensis, T. boylei, and T. ramosus, by having 3 supraorbital pore, discontinuous supraorbital canal, expanded supraorbital tendon bone, and the premaxilla equal in size to, or smaller than, the maxilla. Can be separted from these five species by the following characters: non-enlarged base of the maxillary barbel, thick rugose layer of fatty tissue on the head and body absent; and integument on the surface of the interopercle not covering the odontodes. Can be further differentiated from T. alterus in the only slightly compressed caudal peduncle, presence of dark pigmentation on the area of the body anteroventral to the dorsal-fin origin not covering the odontodes, and the profile of the head from a dorsal view which is not much wider posteriorly than anteriorly; from T. aguarague in having four or five premaxillary tooth rows; from T. belensis in the uniformly brown pigmentation on the body and the lack of dark pigmentation on the basal portions of the caudal-fin rays; from T. boylei in the profile of the head from a dorsal view which is not much wider posteriorly than anteriorly; and from T. ramosus in the distally unbranched barbels of variable width along their length (Ref. 94174).

Dorsal soft rays (total): 1114; Vertebrae: 36

Found in a small, silt-laden stream with 0.2 to 1.0 m depth, 1.0 to 2.5 m width over a sand and rock bottom without aquatic vegetation, flow rate 0.037m3/s, conductivity 0.614 mS/ cm, turbidity 10, dissolved oxygen 4.96 mg/l, and temperature 20°C. Hides under rocks. Feeds on autochthonous benthic macroinvertebrates (dipteran larvae and Ephemeroptera) (Ref. 94174)