The genus Loricaria Linnaeus of the family Loricariidae is diagnosed as a monophyletic group based on two uniquely derived synapomorphies: lower lip surfaces covered with filiform papillae and absence of buccal papillae surrounding the dentary teeth. Loricaria are small to moderate-sized catfishes widely distributed throughout most of the major river drainages of cis-Andean South America, including the Amazon, Orinoco, Paraguay, Paraná, and smaller coastal rivers draining the Guyana and Brazilian Shields. Based on multivariate analyses of morphometric and meristic data in combination with qualitative assessment of external morphological characters, 15 nominal species are accepted as valid, with an additional nine described as new. Among the nominal species, L. lentiginosa is synonymized with L. prolixa. Loricaria carinata is resurrected from synonymy with L. cataphracta and L. simillima is treated as a junior synonym of L. carinata. Formal diagnoses, descriptions, and a key to all 24 species are provided. Phylogenetic analyses of Loricaria and related taxa (Spatuloricaria, Crossoloricaria, Planiloricaria, Brochiloricaria, Paraloricaria, and Ricola) based on a combined data set of 32 gap-coded quantitative (morphometric and meristic) characters and 24 qualitative characters derived from external morphology resulted in fully resolved, but poorly supported phylogenies under equal weights and implied weighting criteria. Implied weights analyses using a concavity constant (K) of 24-49 recovered Loricaria as a monophyletic group with L. piracicabae as basal and sister to six terminal clades containing all other species. Species originally described as Loricaria, but subsequently transferred to Brochiloricaria, Paraloricaria, and Ricola, were recovered as paraphyletic in each analysis and should be treated as congeneric with Loricaria. Distributions of Loricaria exhibit patterns of endemism similar to those documented for other groups of Neotropical fishes. Species diversity is highest in the Amazon basin (13 species, including 10 endemics), followed by the Paraguay region (5 species, including 4 endemics), Guianas region (5 species, including 2 endemics), Orinoco basin (3 species, including 2 endemics), and a single species occurring in both the São Francisco basin and drainages of Northeastern Brazil. Loricaria is apparently absent from coastal Atlantic drainages south of the São Francisco basin. Such shared patterns of endemism provide some insight into past geomorphological processes that have influenced diversification in Loricaria and serves as a foundation for further tests of biogeographic hypotheses based on phylogenetic and geological evidence.

Orientador: Vanessa Doro Abdallah / Resumo: No presente estudo é apresentada uma análise da diversidade de parasitos presentes em peixes da ordem Siluriformes, coletados durante os anos de 2014 a 2016 no rio Batalha, pertencente à bacia hidrográfica do Tietê-Batalha (BH-TB), localizada na Região Centro-Oeste do Estado de São Paulo. Os parasitos de organismos aquáticos, particularmente os de peixes, são subestimados quanto à sua importância no impacto das populações hospedeiras. Tem-se observado um aumento nas pesquisas com esta temática, com estudos mais aprofundados envolvendo a dinâmica populacional destes organismos ao longo do tempo-espaço em hospedeiros em seu ambiente natural, ampliando assim o conhecimento sobre as estratégias de adaptação nas relações parasito-hospedeiro-ambiente. Em regiões impactadas, como é o caso da maioria dos corpos d’água do Estado de São Paulo, e dependendo do tipo de alteração ambiental em seus arredores, toda a cadeia trófica dos organismos aquáticos será influenciada por tais mudanças, e os parasitos responderão mais rapidamente do que os seus hospedeiros a estas alterações. A diversidade de organismos aquáticos no rio Batalha ainda é pouco conhecida com estudos restritos na região, e os peixes da ordem Siluriformes se destacam tanto em riqueza de espécies quanto em abundância, cuja importância se dá nas práticas desportivas, na alimentação local e, principalmente, com finalidade ornamental. São organismos amplamente diversificados e complexos, distribuídos em vários tipos de ambient... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study analyzes the parasites diversity present in fish species of the order Siluriformes, collected during the years 2014 to 2016 in the Batalha River, Tietê-Batalha river basin (BH-TB), in the Central-West Region of the State of São Paulo. Parasites of aquatic organisms, particularly those parasitizing fish, are underestimated as to their importance in the impact of host populations. The studies on this theme has grown over time, with more in-depth studies involving the population dynamics of these organisms over time-space in hosts in their natural environment, thus increasing knowledge on adaptation strategies in parasite-host-environment relationship. In degraded regions, as is the case with most water bodies in the State of São Paulo, and depending on the type of environmental change in their surroundings, the entire trophic chain of aquatic organisms will be influenced by such changes, and the parasites will respond more than your hosts to these changes. The diversity of aquatic organisms in the Batalha River is still little known with restricted studies in the region, and the Siluriformes species stand out both in species richness and in abundance, whose importance is given in sports, local feeding and ornamental purpose. They are widely diversified and complex organisms, distributed in several types of environment, with preference for cloudy water, between rocks and vegetation of the bottom of the rivers, with predominantly nocturnal habits, mainly in trop... (Complete abstract click electronic access below) / Doutor