Revisão taxonômica das espécies de Rineloricaria (Siluriformes: Loricariidae) do Peru

Abstract

The genus Rineloricaria Bleeker (1862) currently comprises 65 valid species that are distributed from Panama in Central America to northern Argentina. Three Rineloricaria species are currently recorded from Peru: Rineloricaria lanceolata, with type locality in the district of "Xeberos" in the department of Loreto, R. morrowi and R. wolfei both species with type locality in the río Ucayali basin in the district Contamana. Peruvian Rineloricaria species are reviewed based on external morphology, osteological features and color pattern. Six species are recognized. The three species were validated and Rineloricaria morrowi and R. wolfei were redescribed. Rineloricaria lanceolata is differentiated by having irregular dark blotches on on all fins and two parallel bands on dorsum of head, by having a higher number of post-rostral plates and the anterior ventral margin of pectoral girdle straight; its distribution mainly comprises río Madre de Dios, río Amazonas and río Ucayali basins and their tributaries. Rineloricaria morrowi is distinguished by having five longitudinal lateral plate series, a dark line along both sides on ventral area of caudal peduncle, a dark spot at anal-fin unbranched ray base and a dark band at the distal region of the caudal; its distribution is restricted to the río Amazonas basin and tributaries. Rineloricaria wolfei, has four longitudinal lateral plate series, triangular head profile and wide dark brown stripe covering the first half of the caudal fin, fifth ceratobranchial pharyngeal tooth plate wider with globular shape (vs. fifth ceratobranchial pharyngeal tooth plate narrow with triangular shape), a set of plates between insertions of pelvic fins anterior to the posterior complex irregularly arranged in more than one row (vs. arranged in one row). Additionally, three new species were described: Rineloricaria sp. "Loreto ", distinguished by a strongly convex snout profile with naked snout tip area reduced to a narrow line and type locality at río Morona basin in Loreto State. Rineloricaria sp. "Madre de Dios" is differentiated from all congeners except from R. fallax by having a conspicuous dar brown spot on nuchal plate (vs. nuchal plate without dark brown spot); it differs from R. fallax by having four longitudinal lateral plate series (vs. five longitudinal lateral plate series), having type locality in the quebrada Wiratkentsa in Loreto State. Rineloricaria sp. "Pasco" is distinguished by having the naked area of snout tip as a globular protuberance and a narrow body, with type locality in Puerto Bermudez at Pasco State. Illustrations of species and osteological characters are presented. The diagnostic characters of the genus are discussed, as well as geographical distribution of Rineloricaria species occurring in Peru and its relationship with highly diverse areas in the Neotropics.