A new species of Aequidens (Cichliformes: Cichlidae) from the rio Paraguai basin, Brazil

Abstract

Abstract Morphological and molecular data support the description of a new Aequidens species from the upper rio Correntes, considered herein as endemic to the upper rio Paraguai basin in the Cerrado biome in Brazil. The new species is distinguished from all congeners, except from A. plagiozonatus by having anteriorly oblique dark brown flank bars vs. vertical flank bars, and is additionally distinguished from some congeners by showing a discontinuous lateral band and presence of a dark cheek spot. The new species differs from Aequidensplagiozonatus by having the profile of the dorsal part of head almost straight (in lateral view), with a conspicuous concavity at the interorbital, and by the longer length of upper and lower jaws. Furthermore, delimitation analyses based on mitochondrial data provide additional support for the validity of the species. Our study data also revealed the occurrence, and consequently the first record, of A.plagiozonatus in the upper rio Araguaia basin, which was most likely driven by headwater capture events.