No abstract

The present paper reports the first record of non-native species Poecilia sphenops Valenciennes, 1846 in northeastern Brazil in rio Sergipe basin, a coastal drainage of the Sergipe state. This species was collected at seven sites in the Caatinga biome. The cause of the introduction is not known, but we believe it is a direct impact of the aquarium trade through the aquarium dumping performed by hobbyists. The presence of P. sphenops in natural waterbodies increases concerns for interference with native ecosystems, and the risk of eggs predation in native species with low fecundity and absence of parental care such as Astyanax lacustris and Serrapinnus heterodon, competition and hybridization with the native poeciliid Poecilia vivipara.

Xyliphius anachoretes, a new species of aspredinid catfish is described from the Tocantins-Araguaia River system. Xyliphius anachoretes is diagnosed by the presence of six developed retrorse serrae on posterior border of pectoral-fin spine, presence of papillae on the lower lip bearing minute branches, and only two dorsal procurrent rays. Comments about the informativeness of character-state variation among Xyliphius species and aspredinid related genera are furnished. Also, a brief discussion about conservation status of the new taxon is made.
Xyliphius anachoretes, uma nova espécie de bagre aspredinídeo é descrita para o sistema Tocantins-Araguaia. Xyliphius anachoretes é diagnosticado pela presença de seis serras retrorsas desenvolvidas na borda posterior do espinho da nadadeira peitoral, presença de papilas no lábio inferior apresentando minúsculas ramificações, e somente dois raios pró-correntes dorsais. Comentários sobre a informação contida na variação de estados de caráter entre as espécies de Xyliphius são fornecidos. Além disso, uma breve discussão sobre o estado de conservação do novo táxon é feita

A new species of Pamphorichthys is described from Preto river, tributary of the São Francisco river drainage. The new species is the sister group of the remaining species of Pamphorichthys, showing synapomorphies of the genus, including the reduced number of gonapophyses and gonapophyses tips parallel to the vertebral spine. The diagnosis is given by the following unique features: outer row of teeth on pre-maxilar and dentarium with bilobed incisive teeth; distal segments of the third ray of the gonopodium and an elongated anterior branch of the fourth ray with a putative origin in the fusion of several distal segments; anterior and posterior branches of gonopodium ray 6 with distal segments fused into only one segment; six dorsal-fin rays in males; and urogenital region of reproductive females with heavy dark pigmentation all around the anus and urogenital opening.