New species of Moenkhausia Eigenmann, 1903 (Characiformes: Characidae) with comments on the Moenkhausia oligolepis species complex

Abstract

A new species of Moenkhausia is described from tributaries of the rio Paraguay, Brazil. The new species is diagnosed from congeners by characters related to body coloration, the number of lateral line scales, the degree of poring of the lateral line, and number of scales rows above and below the lateral line. Molecular analyses using partial sequences of the mitochondrial gene Cytochrome Oxidase I from specimens of the new species and specimens belonging to morphologically similar species demonstrated that the new species is easily differentiated by their high genetic distance and by their position in the phylogenetic hypothesis obtained through the Maximum Parsimony methodology. The analyses of three samples of M. oligolepis also revealed that they have high genetic distances and belong to different monophyletic groups suggesting that this species corresponds to a species complex rather than a single species.Uma nova espécie de Moenkhausia é descrita de tributários do rio Paraguai, Brasil. Essa nova espécie é diagnosticada de seus congêneres por caracteres relacionados ao padrão de colorido do corpo, número de escamas da linha lateral, grau de desenvolvimento dos poros sensoriais na linha lateral e número de séries de escamas acima e abaixo da linha lateral. Um análise molecular usando sequências parciais do gene mitocondrial Citocromo Oxidase I de espécimes representativos da nova espécie e espécimes pertencentes a espécies morfologicamente similares demonstrou que a nova espécie é facilmente diferenciada por sua elevada distância genética e por sua posição na hipótese filogenética obtida pelo método de máxima parcimônia. A análise de três amostras de M. oligolepis também revelou que estas apresentam distâncias genéticas elevadas e pertencem a grupos monofiléticos distintos, sugerindo que esta espécie corresponda a um complexo de espécies e não uma única espécie.

Ecomorphology and use of food resources: inter- and intraspecific relationships of fish fauna associated with macrophyte stands

“…The specimens caught were fixed in 4% formaldehyde and subsequently stored in alcohol 70°GL. The specimens were identified according to Britski et al (2007), Graça & Pavanelli (2007) and Benine et al (2009), labeled, weighed and measured. Only adult individuals were analyzed (Gomiero et al, 2008;Montag et al, 2011), considering that the ontogenetic growth can promote significant changes in morphology (Novakowski et al, 2004;Vitule et al, 2008) or feeding habit (Drewe et al, 2004).…”

Moenkhausia rubra, a new species from rio Juruena, upper rio Tapajós basin, Brazil (Characiformes: Characidae)

“…The genus Moenkhausia Eigenmann currently comprises over seventy valid species (Bertaco et al, 2011a(Bertaco et al, , 2011bMariguela et al, 2013) presenting a wide variation in overall shape and pigmentation patterns (Benine et al, 2004), many of which have been described recently (e.g., Benine et al, 2009;Zanata et al, 2009;Marinho, 2010;Marinho & Langeani, 2010;Sousa et al, 2010;Bertaco et al, 2011aBertaco et al, , 2011b. The genus is widely distributed in South America, being present in coastal drainages of the Guyanas, as well as in the río Orinoco, rio Amazonas, rio Tocantins and Araguaia, rio São Francisco, rio Paraná-Paraguay, and Brazilian eastern drainages (Lima et al, 2003).…”

Two new species of Moenkhausia Eigenmann (Characiformes: Characidae) from Serra do Cachimbo, Pará, Northern Brazil

“…This group was defined by the presence of a distinct reticulate color pattern and a "black bar over the terminal portion of caudal peduncle and basal portion of caudal fin that is preceded by a light area on the caudal peduncle". Lima & Toledo-Piza (2001) described M. dyktiota as possibly related to this assemblage, and more recently two species were added to Costa's (1994) group: M. cosmops (Lima et al, 2007), and M. forestii (Benine et al, 2009). Lima & Birindelli (2006) described Moenkhausia petymbuaba, based on specimens collected in Serra do Cachimbo, which is the main geographical barrier between the middle courses of the rio Xingu and the rio Tapajós, where the headwaters of those drainages lie close to each other and are in some cases only separated by a few meters.…”