New basal ancistrin

[Silurus]

Lujan, NK, JW Armbruster & B Rengifo (2011) A new basal Ancistrini genus and species from the Andes of northern Peru (Siluriformes: Loricariidae). Copeia 2011: 497–502.

Abstract

Etsaputu relictum, a new genus and species sister to all other Ancistrini, is described from the upper Marañon River in Northern Peru. Etsaputu relictum can be diagnosed from all other Hypostominae by having a coracoid with a serrated posterior margin of the posterior process, an opercle with a process extending ventrolaterally from the ventral margin, and branchiostegals one and two fused. Etsaputu relictum is further distinguished by having cheek plates evertible to less than 45° from the sagittal plane, by having fewer than ten (typically zero or six) enlarged cheek-plate odontodes, by having enlarged cheek-plate odontodes straight and no longer than 15 times length of odontodes on lateral body plates, by having large eyes (mean 24.0% of head length, range 21.7–27.6% HL), and by having uniformly gold-brown to bronze base color with golden sheen when alive.