Aposturisoma Isbruecker, Britski, Nijssen & Ortega, 1983ZBK.
Type species: Aposturisoma myriodon Isbruecker, Britski, Nijssen & Ortega, 1983ZBK.
Holotype: MZUSP 15328, Peru, Ucayali Department, Coronel Portillo Province,
Rio Aguaytia drainage, Rio Huacamayo at Tingo Maria
This monotypic genus is only known from its type locality and few data are presently available. This is a rheophilic species that has been collected with representatives of the genus ChaetostomaZBK ( Isbrücker et al. 1983). Evers & Seidel (2005) described the habitat of Aposturisoma myriodonZBK as clear, with swift current and shallow waters. They noticed that AposturisomaZBK frequentes areas with rubble substrates in this biotope. Its morphology is similar to that of FarlowellaZBK, to which it is closely related because of the numerous predorsal plates and the origin of the dorsal fin in front of the origin of the anal fin. Nevertheless it has a larger mouth, a much deeper and wider body and a much thicker caudal peduncle which can be interpreted as an adaptation to stream habitat, as this kind of adaptations is also found in rheophilic fishes of the genus ChaetostomaZBK, rather than an intermediary between FarlowellaZBK and Sturisoma as supposed by Isbrücker et al. (1983), these two genera not being particularly rheophilic.