Guillermo Enrique Terán, Juliano Ferrer, Mauricio Benitez, Felipe Alonso, Gastón Aguilera  & Juan Marcos Mirande.

Abstract

A new species assigned to the genus Trichomycterus from the area of the waterfalls of Tabay stream, Paraná River basin, Misiones, Argentina, is described. Trichomycterus ytororo sp. nov. is distinguished from all other species in the genus by the presence of 31–35 dorsal procurrent caudal-fin rays and the combination of some external characters such as: coloration, number of pectoral–fin rays and pores of the laterosensory canals. The new taxon belongs to a presumably monophyletic group of species composed of T. crassicaudatus, T. igobi, and T. stawiarski based on the presence of 24 or more thickly ossified and rigid procurrent caudal-fin rays with a slender distal tip extending along the tips of at least ten neural spines.

Artigo completo: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0179594

Fig 1. Trichomycterus ytororo, holotype, CI–FML 7240, 94.2 mm SL; Argentina, Misiones Province, Jardín América, Tabay stream, Paraná River basin.

Fig 4. Geographic distribution of the species assigned to the Trichomycterus stawiarski group: T. crassicaudatus (green symbols), T. igobi (white symbols), T. stawiarski (yellow symbols) and T. ytororo (red symbol). Stars represent the type localities. Some triangles symbols represent more than one collection locality. Numbers 1, 2, 3 indicate the Paraguay, Paraná and Iguazú Rivers, respectively.