A systematic review of Planaltina (Teleostei: Characiformes: Characidae: Glandulocaudinae: Diapomini) with a description of two new species from the upper rio Parana, Brazil

摘要

Two new species, Planaltina glandipedis and Planaltina britskii, glandulocaudine fishes of the family Characidae, tribe Diapomini, are described herein. They were collected from tributaries of the rio Grande and or the rio Tiete, both tributaries of the upper rio Parana in the State of Sao Paulo, Brazil. The previously described species, Planaltina myersi, until now known almost exclusively from the holotype, is here redescribed from 47 specimens taken from tributaries of the rio Corumba, a tributary of the upper rio Parana. The two new species differ most prominently from the previously known species by possession of three somewhat elongate scales along the dorsal border of the male's caudal pouch opening. There is only one elongate scale in P. myersi. Planaltina glandipedis differs from P. britskii in having six or seven horizontal scale rows between the dorsal-fin origin and the lateral line versus five in the later species. The possible phylogenetic relationships among the three inseminating species within the tribe Diapomini, subfamily Glandulocaudinae, are discussed along with the putative phylogenetic relationships of the Diapomini to the newly recognized glandulocaudine outgroup containing the characid genera Knodus and a new genus related to Attonitus. Brief comments are presented concerning the geographical distribution and ecology of the species of Planaltina.