A new species of the Hoplias malabaricus species complex (Characiformes: Erythrinidae) from the La Plata River basin

JUAN JOSE ROSSO; EZEQUIEL MABRAGAÑA; MARIANO CASTRO; MATIAS S. DELPANI; ESTEBAN AVIGLIANO; NAHUEL SCHENONE; JUAN MARTÍN DÍAZ DE ASTARLOA

CYBIUM

SOC FRANCAISE D ICHTYOLOGIE

Lugar: Paris; Año: 2016 vol. 40 p. 199 - 208

0399-0974

Hoplias malabaricus corresponds to a species complex comprisingdifferent evolutionary units resulting in seven distinct karyomorphs. Thespecies-level genetic divergence within Hopliasmalabaricus may not be restricted to different karyomorphs, but even amongindividuals sharing the same karyomorph. It is therefore imperative, to conducttaxonomical studies intended to characterizes the different haplotypes detectedwithin the karyomorphs of Hopliasmalabaricus. In this paper we tested for species diversity within the genusHoplias of the lower Plata River Basinusing DNA Barcoding and further characterize different genetic units within theHoplias malabaricus group. We collected42 specimens of Hoplias, 32 belongingto the H. malabaricus group and 10 to the H. lacerdae group, 5 H.lacerdae and 5 H. australis. The K2P genetic distances averaged0.27% within species and 11.7% within genus. Character-based analysis of nucleotidecomposition detected 48 base positions as be relevant for speciesdiscrimination in Hoplias of thelower Plata Basin. DNA Barcoding revealed the existence of 3 different BINswithin the H. malabaricus speciesgroup together with one BIN for each species of the H. lacerdae group. Specimens from one BIN of Hoplias malabaricus showed a unique combination of characters amongall known species of the genus Hoplias.In consequence, we formally described here a new species of Hoplias within the H. malabaricus group.