A comprehensive phylogeny of species relationships of the Auchenipteridae is reconstructed here with a large-scale taxon sampling based on combined morphological and molecular datasets. The hypothesized phylogeny includes most species of Auchenipteridae (97 of 124 valid species) and multiple members of siluriform families as an outgroup (32 species) to embrace the diversity of forms among related catfishes. As the first large-scale phylogeny of the Auchenipteridae, comparison between taxa included information from both morphology (264 characters) and mitochondrial and nuclear molecular markers (3490 nucleotides) from five genes: coI, 16S, rag2, myh6 and SH3PX3. Trees were generated under two different optimality criteria (Maximum Parsimony and Bayesian Inference). A new classification for the family is presented herein to bring the taxonomy more in line with the new phylogenetic hypothesis. The strict consensus tree corroborates the monophyly of superfamily Doradoidea, family Auchenipteridae and its two subfamilies, Centromochlinae and Auchenipterinae. The new classification scheme proposes nine tribes in Auchenipteridae, based on the monophyly of major groups in both subfamilies. Centromochlus, Glanidium and Tatia are each recovered as paraphyletic. To maintain a monophyletic classification, some species treated as Tatia and Centromochlus are assigned to genera not previously recognized as valid.

Otothyropsis piribebuy, new species, is described from the río Piribebuy, a tributary to the río Paraguay basin, Cordillera, Paraguay. The new species is distinguished from O. marapoama mainly by having a continuous mid-dorsal series of 17-18 lateral plates, a robust levator crest in the hyomandibula, naked areas in the abdomen, an unpigmented circular blotch on the median portion of the lower lobe, and by several features related to sexual dimorphism. In addition, Otothyropsis is rediagnosed and its phylogenetic relationships are discussed based on its present diversity.Otothyropsis piribebuy, espécie nueva, es descrita del río Piribebuy, cuenca del río Paraguay, Departamento de Cordillera, en Paraguay. La espécie nueva es diferenciada de O. marapoama principalmente por presentar una serie continua de 17 a 18 placas laterales médio-dorsales, cresta levator robusta en la hiomandíbula, abdomen con áreas desnudas, ausencia de pigmentación en la región media del lóbulo inferior con formato circular, y por la presencia de diversas características de dimorfismo sexual. Adicionalmente, es presentada una rediagnosis para Otothyropsis, discutida sus relaciones filogenéticas y su actual diversidad.

Analysis of specimens of the auchenipterid catfish genus Tatia collected in the rio Teles Pires, a tributary of the rio Tapajós, along the border between the states of Pará and Mato Grosso, Brazil, revealed it to be an undescribed species. This new species is distinguished from all congeners with the exception of T. carolae and T. musaica by the intense, clearly demarcated, dark coloration on the dorsal and to varying degrees lateral and sometimes ventrolateral portions of the body versus the very lightly colored regions which are translucent in life on the remainder of the body. Various details of head, body and dorsal and caudal-fin pigmentation along with meristic and morphometric features distinguish the new species from T. carolae and T. musaica. The new species provides further evidence that the upper and middle rio Tapajós is a region of ichthyofaunal endemism.A análise de espécimes do bagre auquenipterídeo do gênero Tatia, provenientes do rio Teles Pires, um tributário do rio Tapajós, na divisa entre os estados do Pará e Mato Grosso, Brasil, revelou se tratar de uma espécie ainda não descrita. Esta espécie nova distingue-se de seus congêneres, com exceção de T. carolae e T. musaica, por sua intensa e distintamente demarcada, coloração escura sobre o dorso a variados graus na porção lateral e algumas vezes ventro-lateral do corpo em contraste com regiões de coloração muito clara, a qual é translúcida em vida, no restante do corpo. Vários detalhes da pigmentação da cabeça, corpo, e nadadeira caudal e dorsal juntamente com características merísticas e morfométricas distinguem a espécie nova de T. carolae e T. musaica. A espécie nova fornece evidência adicional de que a porção alta e média da bacia do rio Tapajós é uma região de endemismo da ictiofauna.

A new species of Curculionichthys is described from the rio Curuá-Una basin, in the northern edge of the Brazilian Shield, State of Pará, Brazil. The new species is diagnosed from congeners by possessing a single rostral plate, by having darkened tooth-crowns, and by a series of morphometric and meristic data. A close examination of the species of Curculionichthys revealed the presence of hyperthrophied odontodes on both dorsal and ventral margins of the snout tip, which are illustrated by electronic microscopy. A discussion is provided on possible phylogenetic relationships of the new taxon. The new species is provisionally accessed as Least Concern (not threatened).

Otothyropsis polyodon, sp. n., and O. biamnicus, sp. n., two new species of loricariid catfishes are described from the rio Paraná basin. Otothyropsis biamnicus and O. polyodon differ from two other Otothyropsis by having a longer caudal peduncle, middle series of lateral plates complete and with higher number of plates, and the anterior margin of the mesethmoid not covered by median rostral plate ventrally. The new species differ from each other in that O. polyodon have a longer pectoral-fin spine and a greater number of premaxillary and dentary teeth. Otothyropsis polyodon was collected in the rio Verde, tributary to the upper rio Paraná basin, and O. biamnicus is found in both the rio Iguaçu and rio Tibagi basins. A key for the species of Otothyropsis is presented and their relationships and geographical distributions are discussed.Key words: Neotropical, Catfish, Systematics, Biogeography, Hisonotus, Genetype ResumoOtothyropsis biamnicus, sp. n., e O. polyodon, sp. n., duas novas espécies de cascudinhos são descritos da bacia do rio Paraná. Otothyropsis biamnicus e O. polyodon diferem dos outros Otothyropsis por ter maior comprimento do pedúnculo caudal, série média de placas laterais completa e com maior número de placas e a margem anterior do mesetmóide não coberta pela placa rostral ventralmente. As novas espécies diferem entre si por O. polyodon possuir o espinho da nadadeira peitoral mais longo e maior número de dentes na pré-maxila e dentário. Otothyropsis polyodon foi coletado no rio Verde tributário da bacia do rio Paraná superior e O. biamnicus é encontrado nas bacias do rio Iguaçu e do rio Tibagi. Uma chave para as espécies do gênero Otothyropsis é apresentada e suas relações e distribuição geográfica são discutidas.

Previously proposed synapomorphies for the genus Gelanoglanis of the catfish family Auchenipteridae are evaluated and four additional features involving the relationship between the mesethmoid and premaxilla, the very fleshy anterior portion of the snout, the lack of ossification of the second through fourth infraorbitals, and the incomplete poring of the lateral line are hypothesized as synapomorphic for the members of the genus. A new species of Gelanoglanis is described based on a series of specimens collected in the rio Teles Pires, a tributary of the rio Tapajós in the southern reaches of the Amazon basin. The new species demonstrates a number of features unusual within Gelanoglanis including a fontanel bordered by the frontals, a particularly elongate gonopodium in mature males, reductions in the dentition on the premaxilla, and a shorter posterior extension of the maxilla inside the maxillary barbel. The new species is a miniature as evidenced both by its body size and the reductions of various ossifications of the head, the number of fin rays and of the laterosensory canal system on the head and body.Sinapomorfias propostas previamente para o gênero Gelanoglanis da família Auchenipteridae são avaliadas e quatro características adicionais que envolvem a relação entre o mesetmóide e a pré-maxila, a porção anterior do focinho carnosa, a perda de ossificação do segundo ao quarto infraorbital e linha lateral incompleta são hipotetizadas como sinapomórficas para os membros do gênero. Uma espécie nova de Gelanoglanis é descrita com base em uma série de exemplares coletados no rio Teles Pires, um tributário do rio Tapajós na porção sul da bacia Amazônica. A espécie nova possui várias características incomuns dentro de Gelanoglanis, incluindo uma fontanela bordeada pelos frontais, um gonopódio particularmente longo em machos maduros, redução da dentição na premaxila, e extensão posterior da maxila mais curta dentro do barbilhão maxilar. A espécie nova é uma miniatura, como evidenciado não apenas pelo tamanho reduzido do corpo, como também pela redução da ossificação da cabeça, do número de raios e do sistema de canais látero-sensoriais da cabeça e do tronco.

The Neotropics harbour the greatest diversity of freshwater fish on Earth. Despite recent advances in characterizing the fish fauna, the total number of species, distributional range, evolution and ecological traits remain uncertain. Thus, we quantify shortfalls in the knowledge of taxonomy (Linnean shortfall), geographic distribution (Wallacean shortfall), evolutionary relationships (Darwinian shortfall) and feeding habits (Raunkiaeran shortfall) of Auchenipteridae driftwood catfishes, one of the most representative groups of the Siluriformes family in the Neotropics. We find a

A new species of Gelanoglanis is described based on specimens collected in the Tocantins River, a tributary of the Amazon Basin. The new species is distinguished from congeners by unusual features to the genus such as the pelvic fin falling short of the urogenital opening by a distance larger than the anal-fin length, the first unbranched dorsal and pectoral-fin rays not ossified as spines, the dorsal-fin spinelet absent and the adipose fin in adults preceded by a long fleshy ridge. The new species is further distinguished from congeners by its soft, sinuous snout tip and morphometric proportions of the body and head. The new species shares most putative synapomorphies of the genus, as well as the miniaturized condition evidenced by a diminutive body size and reduced ossifications and lateral sensory system. An elongate dorsal process of the cleithrum is posited as an additional synapomorphy for the genus. An osteological description of Gelanoglanis nanonocticolus based on high-resolution X-ray computed tomography is also provided. http://zoobank.org/urn:lsid:zoobank.org:pub:BA3FE72D-FEF84-7A7-B751-2A15EA52C203.