Análise de evidência total da Tribo Harttiini sensu Isbrücker, com uma revisão taxonômica de Sturisomatichthys Isbrücker & Nijssen, 1979

Abstract

A total evidence analysis of the Harttiini sensu Isbrücker is presented. Ten genera historically included in the tribe are assumed as ingroup in the present analysis, which comprises: Aposturisoma, Cteniloricaria, Farlowella, Harttia, Harttiella, Lamontichthys, Metaloricaria, Pterosturisoma, Sturisoma and Sturisomatichthys. The ingroup encompasses 78 terminal taxa plus 22 belonging to the outgroup which were chosen from other subfamilies of the Loricariidae and genera of the Loricariini. Seven molecular markers were included for the phylogenetic analysis, the mitochondrial Cytb, nd2, 12S and 16S, and the nuclear MyH6, RAG1 and RAG2. Additionally, 216 morphological characters are included, which encompasses characters proposed by previous authors and new characters proposed herein including both osteology and external morphology. A Maximum Parsimony analysis and a Bayesian Inference analyses were carried out using the concatenated matrix which is comprised by 6,839 characters. Thirty most parsimonious trees were found with a length of 18.254 steps, consistency index (CI) of 0.37 and retention index (RI) of 0.59, a consensus tree was obtained and showed a paraphyletic Harttiini sensu Isbrücker; the same result was obtained from the Bayesian Inference analysis. Harttiini comprises Harttia, Harttiella and Cteniloricaria. Farlowellina is elevated to the tribe rank as Farlowellini, encompassing Farlowella, Lamontichthys, Pterosturisoma, Sturisoma and Sturisomatichthys; Aposturisoma is here suggested as junior synonym of Farlowella. Metaloricaria is assigned to the monotypic Metaloricariini. On the other hand, the Loricariini is here restricted to a unique group without a subtribal division, contrary to what was proposed in previous studies. Sturisoma was corroborated here to be strictly cis-Andean, while Sturisomatichthys encompasses, besides the valid species already included in the genus, the trans-Andean species belonging to Sturisoma sensu lato. Two new species of the former and one new species of the latter were recognized. A new classification for the Loricariinae is offered, as well as for identification keys for the genera of both the Harttiini and the Farlowellini. Discussions regarding the taxonomy of the genera found to be valid are offered. Furthermore, a taxonomic revision of Sturisomatichthys is presented. A total of 358 specimens including both type an non-type specimens of all valid species were examined. Sturisomatichthys was found to encompass 12 valid species: Sturisomatichthys aureus, S. caquetae, S. citurensis, S. dariensis, S. festivus, S. frenatus, S. kneri, S. leightoni, S. panamensis, S. tamanae. In addition, two new species are described, Sturisomatichthys Baudó n.sp. from the Baudó River, in Northwestern Colombia, belonging to the Caribbean slope of the continent, and Sturisomatichthys San Juan n.sp. from the San Juan River basin in western Colombia, on the Pacific slope. Sturisomatichthys caquetae, from the Morelia River, upper Amazon, is transferred back from Sturisoma and S. leightoni is distributed, besides the Magdalena-Cauca basin, in the Orinoco basin; thus, Sturisomatichthys is discovered to be distributed in both trans- and cis-Andean drainages. A neotype is designated for S. aureus from the Lower Magdalena basin, type locality of the species. New records of localities in the Northwestern region of South America, as well as the redescription and taxonomic comments of all valid species, are provided. Maps with the distribution of the genus and a key of identification of the species are provided.