trichomycterine catfishes, Bleeker, 1858

Costa, Wilson J. E. M., Barbosa, Maria Anaïs & Katz, Axel M., 2024, Two new species of Trichomycterus (Siluriformes: Trichomycteridae) from the Rio Itabapoana Basin, south-eastern Brazil, European Journal of Taxonomy 970, pp. 122-137 : 134

Key to the identification of trichomycterine catfishes from the Rio Itabapoana Basin

1. Flank with minute dark brown dots on its entire surface, never forming large spots or broad stripes; seven pectoral-fin rays ...................................................................................................................... 2

– Flank with large spots or broad stripes; eight pectoral-fin rays ........................................................ 3

2. Nasal barbel posteriorly area anterior to opercular patch of odontodes; pectoral-fin filament about 10% of pectoral-fin length or less;dorsal procurrent caudal-fin rays20or21;flank with sparse dark brown dots that are separated among themselves by large interspaces T. (Cryptocambeva) berthalutzae sp. nov.

– Nasal barbel posteriorly reaching opercular patch of odontodes; pectoral-fin filament about 20–25% of pectoral-fin length; dorsal procurrent caudal-fin rays 17–19; flank with highly overlapped dots. .......................................................................... T. (Cryptocambeva) brunoi Barbosa & Costa, 2010

3. Flank with broad longitudinal dark brown stripe on midline; caudal fin rounded, asymmetrical, with dorsal portion longer than ventral portion; paired s6 pore T. (Psammocambeva) fabioheppi sp. nov.

– Flank with longitudinal rows of dark brown blotches; caudal fin subtruncate, symmetrical; single median s6 pore .................................................................................................................................. 4

4. Maxillary barbel reaching between interopercle and pectoral-fin base; pectoral-fin filament about 40–50% of pectoral-fin length; premaxillary teeth 30–34, dentary teeth 38–41 ................................ .......................................................... T. (Psammocambeva) caudofasciatus Alencar & Costa, 2004

– Maxillary barbel reaching interopercle; pectoral-fin filament about 10–20% of pectoral-fin length; premaxillary teeth 43–46, dentary teeth 51–54 .. T. (Psammocambeva) mimosensis Barbosa, 2013