A new endemic species of Bryconamericus (Characiformes, Characidae) from the Middle Cauca River Basin, Colombia

C Román–Valencia,R I Ruiz-C,D C Taphorn,C García-Alzate

doi:10.32800/abc.2014.37.0107

Abstract

Bryconamericus caldasi, a new species, is described from the Middle Cauca River drainage, Andean versant of Colombia. The new species is distinguished from all congeners by: the number of predorsal scales (15–17 vs. 9–14); a wide anterior maxilla tooth, at least twice as wide as the posterior tooth, both of which are pentacuspid (vs. maxilla teeth of same size); a dark lateral stripe overlaid by a peduncular spot; and a reticulated pattern on the sides of body (vs. peduncular spot and other body pigments not superimposed over a dark lateral stripe). We found several differences that distinguish the new species from B. caucanus, the only sympatric congener: number of predorsal median scales (15–17 vs. 12–13); convex predorsal profile (vs. oblique); scale size and number of scale rows at caudal–fin base (small scales arranged in two or more rows vs. large scales in just one row); pectoral fins not or just reaching pelvic fin insertions (vs. pectoral fins reaching posterior to pelvic–fin insertions); and dorsal–fin origin position (at vertical through posterior tip of pelvic–fin vs. at a vertical anterior to pelvic–fin tip).

Highlights

79 species are assigned to the genus Bryconamericus (Román–Valencia et al, 2008; Eschmeyer & Fricke, 2013)
The known distribution of Bryconamericus in Colombia suggests that this genus is more diverse in Transandean than in Cisandean drainages, probably because of several geographic isolation events (Román–Valencia et al, 2009b).The description of this new species of Bryconamericus from the Middle Cauca River Basin is a result of our ongoing revision of the genus, and is further evidence of the undocumented biodiversity of Bryconamericus
Diagnosis Bryconamericus caldasi is distinguished from most congeners by having a dark lateral stripe overlaid by a peduncular spot and reticulated pattern on the sides of the body; by the predorsal scale counts (15–17 vs. 9–14, except B. andresoi with 13–15, B. galvisi with 12–17, B. huilae with 14–19, B. plutarcoi and B. foncensis with 11–16); and a wide anterior maxilla tooth, at least twice as wide as the posterior tooth, both of which are pentacuspid

Summary

Introduction

79 species are assigned to the genus Bryconamericus (Román–Valencia et al, 2008; Eschmeyer & Fricke, 2013). 22 valid species occur in Colombian watersheds (Román–Valencia et al, 2008, 2009a, 2009b, 2010, 2011, 2013), but only one species, B. caucanus, has been reported from the Río Cauca (Román–Valencia et al.,2009a), and it is known to have a wide geographic distribution in Colombia (Román–Valencia, 2003; Román–Valencia et al, 2009a). The known distribution of Bryconamericus in Colombia suggests that this genus is more diverse in Transandean than in Cisandean drainages, probably because of several geographic isolation events (Román–Valencia et al, 2009b).The description of this new species of Bryconamericus from the Middle Cauca River Basin is a result of our ongoing revision of the genus, and is further evidence of the undocumented biodiversity of Bryconamericus

Material and methods

Findings

Discussion