Official websites use. Share sensitive information only on official, secure websites. A phylogenetic analysis using fragments of two nuclear and two mitochondrial genes strongly supported sister group relationships between a new species and Trichomycterus albinotatus , corroborated by unique colour patterns of adult specimens and juveniles, and morphology of the autopalatine bone.
The new species is distinguished from its closest congener, T. Both the new species and T. Trichomycterus albinotatus is endemic to an area about km across, in the upper section of the Rio Preto that drains the Itatiaia Massif.
However, both species are only known from localities above m asl, suggesting that they cannot survive in ecological conditions at lower altitudes. This study indicates that efforts are necessary to provide more accurate data on the species diversity and distribution of Trichomycterus in the biologically diverse and endangered Atlantic Forest of south-eastern Brazil.
The Atlantic Forest is one of the largest and most biodiverse phytogeographical provinces in the Americas, encompassing about million ha Ribeiro et al. Over fish species, belonging to 89 genera and 21 families Abilhoa et al. Among fish taxa occurring in this province, catfishes of the Trichomycteridae is one of the most interesting and species-rich freshwater groups. It includes small to medium size fishes, never surpassing mm of standard length SL , with members easily identified by a modified opercular system with integumentary teeth in the interopercle and opercle bones Baskin ; de Pinna The mouth is typically subterminal to fully ventral, but in parasitic forms the lips can form a ventral sucking disk Baskin The high diversity in trichomycterids comprises about species in 42 valid genera Fricke et al.
In the Atlantic Forest, Trichomycterus Valenciennes, is the most diversified trichomycterid genus and recently has been restricted to about 50 valid species occurring in an area encompassing eastern and north-eastern Brazil Katz et al. Most species of Trichomycterus were described after , but many new species are still waiting for formal descriptions. For example, the species described here was first collected by one of us WJEMC in and , but due to the scarcity of adult specimens then found, a formal description was not previously concluded.
