somnians, Heptapterus Mees [G. F.] 1974:184, Fig. 36 [Zoologische Verhandelingen (Leiden) No. 132; ref. 2969] Sangadina, tributary of Rio das Mortes, 2 kilometers from Xaventina, Mato Grosso State, Brazil. Holotype (unique): BMNH 1971.7.29.4. Type catalog: Ferraris 2007:189 [ref. 29155]. •Valid as Heptapterus somnians Mees 1974 -- (Burgess 1989:277 [ref. 12860]). •Valid as Phenacorhamdia somnians (Mees 1974) -- (Britski 1993:45 [ref. 21110], Burgess & Finley 1996:167 [ref. 22901], Zarske 1998:30 [ref. 23981], Bockmann & Guazzelli in Reis et al. 2003:416 [ref. 27061], Ferraris 2007:189 [ref. 29155], DoNascimiento & Milani 2008:165 [ref. 29737], Silva 2020:281 [ref. 37978]). Current status: Valid as Phenacorhamdia somnians (Mees 1974). Heptapteridae: Heptapterinae. Distribution: Das Mortes River drainage, Araguaia River basin, Mato Grosso State, Brazil. Habitat: freshwater.