RESUMEN
The genus Zungaro contains some of the largest catfish in South America. Two valid species are currently recognized: Zungaro jahu, inhabiting the Paraná and Paraguay basins, and Zungaro zungaro, occurring in the Amazonas and Orinoco basins. Analysing Zungaro specimens from the Amazonas, Orinoco, Paraguay and Paraná basins, based on the sequencing of COI and D-loop, we found at least three MOTUs, indicating the existence of hidden diversity within this fish group. Considering the ecological and economic values of this fish, our results are surely welcomed for its conservation, disclosing new findings on its diversity and pointing out the necessity for a detailed taxonomic revision.
Asunto(s)
Bagres/genética , Filogenia , Polimorfismo Genético , Animales , Bagres/clasificación , Complejo IV de Transporte de Electrones/química , Complejo IV de Transporte de Electrones/genética , Proteínas de Peces/química , Proteínas de Peces/genéticaRESUMEN
Two new species of Hisonotus are described from the rio Paraná-Paraguay basin in Brazil. The most remarkable features of the new species are the odontodes forming longitudinally aligned rows (one odontode after the other, but not necessarily forming parallel series) on the head and trunk (vs. odontodes not forming longitudinally aligned rows), a pair of rostral plates at the tip of the snout (vs. a single rostral plate), the functional v-shaped spinelet (vs. spinelet non-functional, square-shaped, or absent). These features suggest close phylogenetic relationships with Hisonotus bockmanni, H. insperatus, H. luteofrenatus and H. piracanjuba. Additionally, both new species are distinguished from their congeners by characters related to head length and depth, orbital diameter, suborbital depth, caudal peduncle depth, pectoral-fin spine length, snout length and counts of teeth. Hisonotus paresi sp. n. further differs from its congeners by having contrasting dark geometric spots on the anterodorsal region of the body, a character lacking in H. oliveirai sp. n. The variation in number and shape of the rostral plate, posterior rostrum plates, infraorbitals and the preopercle in both new species and in H. insperatus are discussed.
RESUMEN
A new species of Moenkhausia is described from tributaries of the upper rio Sepotuba, Paraguay basin, Brazil. The new species is distinguished from its congeners by a combination of characters, including an inconspicuous oval-shaped vertically elongated humeral blotch, extending horizontally from third through five lateral-line scales, and vertically from third row above lateral line to first row below it, followed by a diffuse field of dark chromatophores in the flank, combined with a well-defined dark line at the base of the anal fin. Furthermore, the phylogenetic position of the new species is presented based on molecular data, showing a close relationship among species of Moenkhausia and Hemigrammus that have a well-defined dark line at the base of the anal fin. Until this moment, this species is only known from in the upper rio Sepotuba basin.(AU)
Uma nova espécie de Moenkhausia é descrita nos afluentes do rio Sepotuba, bacia do Paraguai, no Brasil. A nova espécie se distingue dos seus congêneres por uma combinação de caracteres, incluindo uma mancha umeral discreta de forma oval, alongada verticalmente, que se estende horizontalmente da terceira a quinta escamas da linha lateral e, verticalmente, da terceira fila de escamas acima da linha lateral até a primeira fila abaixo da linha lateral; seguida por escassos cromatóforos no flanco, combinado com uma linha escura bem definida na base da nadadeira anal. Além disso, a posição filogenética da nova espécie é apresentada com base em dados moleculares, mostrando um relacionamento próximo entre as espécies de Moenkhausia e Hemigrammus que possuem uma linha escura bem definida na base da nadadeira anal. Até o momento, essa espécie é conhecida apenas da bacia do Alto Sepotuba.(AU)