Search

Cambeva piraquara, sp. nov., a restricted-range and rare species last collected from over 20 years ago, is described from the Rio Piraquara, upper Rio Iguaçu basin, Rio Paraná (La Plata) system. The new species is distinguished from all congeners by having two conspicuous dark-brown longitudinal stripes on the inner skin layer of body over a plain yellowish background: a conspicuous wide and well-defined dark-brown longitudinal mid-lateral stripe extending from the opercular patch of odontodes to the first third of caudal-fin rays and a dorso-sagittal stripe comprising large and coalescent rounded blotches extending from occipital to the dorsal-fin base. We provide an illustrated osteological description and assess the conservation status of the new species, which faces several environmental impacts in the upper Rio Iguaçu basin.

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.

A new species of Trichomycterus endemic to the Ribeira de Iguape River basin, southeastern Brazil, was studied based on morphological and molecular evidence. This species had an outer layer of coloration composed of scattered, round, black or dark-brown spots smaller or equivalent in size to the circumference of the eye; eight pectoral-fin rays; 28-29 opercular odontodes; 54-56 interopercular odontodes; and supraorbital line of the laterosensory system not interrupted, with pores s2 absent. Two other species of Trichomycterus from the Ribeira de Iguape River basin are recorded, and their taxonomic status is discussed: Trichomycterus alternatus and Trichomycterus jacupiranga were not differentiated using molecular analysis but may be consistently distinguished based on morphology. The phylogenetic relationships of the co-occurring species, T. alternatus and Cambeva zonata, were inferred using mitochondrial data, reinforcing the taxonomic status of these recently revised species that have a complex taxonomy. In addition, a new combination for Trichomycterus taroba with its inclusion in the genus Cambeva is recommended.

We report the occurrence of an invasive alien species, palometa Serrasalmus maculatus, in the Patos Lagoon drainage. Primary occurrence data were based on three specimens captured and preserved as vouchers in scientific collections. Additionally, we searched for secondary records from unpublished scientific sources, public agencies reports and media news to find additional reports. We discussed the possible pathways of invasion, suggesting as the vector of introduction transpositions from the Uruguay River basin. Ecological implications for ichthyofauna, environmental impacts and risk of other events of invasion in the adjoining basins are discussed.

This work aimed to describe Cambeva cauim, sp. nov., endemic to the Rio Iguacu basin, Brazil and redescribe Cambeva stawiarski using external and internal morphological data through the revision of specimens deposited in fish collections including the type material. In this process, we have also added comments on the possible type locality of C. stawiarski. Cambeva cauim, sp. nov. and C. stawiarski are mainly diagnosed by the anatomy and number of procurrent caudal-fin rays in addition to colouration and several meristic and morphometric characters. Both species are compared with other possibly related species and their synapomorphic characters are discussed. Cambeva cauim, sp. nov. and C. stawiarski along with other eight congeners are endemic to the Rio Iguacu basin, a high impacted freshwater region which could be considered as a biodiversity hotspot to the genus.

A new species of the subtribe Cynopoecilina is described from the rio Gravatai basin, laguna dos Patos system, southern Brazil. The relationships of the new species among taxa of the subtribe Cynopoecilina is discussed based on two analyses: one using 71 discrete characters and other with the addition of six continuous characters analyzed without discretization. The addition of the continuous characters resulted in the first fully resolved phylogenies for Cynopoecilus and Leptolebias species, not obtained in the analysis including only discrete characters. The new species is assigned to Cynopoecilus as sister group to the remaining species of the genus. A new diagnosis is proposed for Cynopoecilus to accommodate the new species. The resulting phylogeny indicates that the occupation of the grasslands of the Pampa biome by the species of Cynopoecilus occurred along the evolution of the genus and that this event was significant for the diversification of the genus. © 2014 The Linnean Society of London

Specimens presently identified as belonging to Odontesthes perugiae species group from rio Parana, rio Uruguay and rio Negro in Argentina, Brazil and Uruguay are revised. Two species are recognized: Odontesthes perugiae , type species of the genus with Odontesthes orientalis as a junior synonym, and a new species described herein. Odontesthes perugiae is redescribed and its distribution restricted to the lower rio Parana, lower rio Uruguay and rio Negro basins. The new species is endemic from the upper rio Uruguay above Salto do Yucuma (Brazil) or Saltos del Mocona (Argentina) falls. Both species share with the remaining taxa included in the O. perugiae species-group ( O. bicudo , O. ledae , O. mirinensis , and O. piquava ) the possession of teeth of the outer row on dentary and premaxilla shorter than those in the inner row, being distinguished from them by the number of gill rakers, body measurements and some osteological characters.

We herein analyse the history of the description of the freshwater fish fauna from three drainages in one of the most densely collected areas of Brazil, and possibly of South America, the Rio Grande do Sul State, southern Brazil. An updated inventory of the freshwater fish species from rio Uruguay (partial) in Brazil, Laguna dos Patos (complete) and rio Tramandaí basins (complete) is presented. We found the number of new species described in these drainages increased nearly 56% since 1981, reaching a total of 422 species, but even now 10% of this number still corresponds to undescribed species. This rate of species description suggests that previous estimates of the Neotropical fish fauna are low, and we predict a final number of Neotropical fishes larger than the largest prediction estimate (8,000 species), after other regions of South and Central Americas become densely sampled. We discuss and attempt to demonstrate that species diversity knowledge is historically and strictly related to collecting efforts. We also demonstrate that the ecoregions in eastern South America with the highest density of species per area correspond to the areas more densely sampled in collections, and this may represent a bias in such kinds of analyses. This uneven sampling in Brazilian regions is apparently associated with the uneven distribution of Zoological research centers in different regions of the country. Small-sized species represents an important source of new species, along with little explored regions or little explored habitats, sometimes associated with restricted range species, and species complexes that need revisionary work. In contrast to other Neotropical regions, Atheriniformes are relatively diverse, sharing the fifth place in species richness with Gymnotiformes, and there is a remarkably high number of species of Rivulidae. Eight species are endemic to the rio Tramandaí drainage, 68 to the Laguna dos Patos system, and 78 to the rio Uruguay drainage. Almost 10% of the freshwater fish species are "Critically Endangered", "Endangered" or "Vulnerable" according to the IUCN criteria, with Rivulidae as the family with the largest number of threatened species.

Listrura depinnai, new species, is described from a small swampy area belonging to Laguna dos Patos system, Municipality of Viamao, Rio Grande do Sul state, southern Brazil. It occurs within the wildlife reserve Refugio de Vida Silvestre Banhado dos Pachecos, and represents the southernmost record of the glanapterygine catfishes. The new species is easily distinguished from remaining Listrura by having the following putative autapomorphies: the region below the midline of flank covered by several spots (vs. unpigmented or with a slender row of small spots); the caudal peduncle at procurrent-ray folds deeper than the preanal portion of body (vs. approximately the same depth); and the presence of a conspicuous intumescence adjacent to the posterodorsal margin of the pectoral-fin base (vs. swelling slight or absent). Putative phylogenetic positions of Listrura depinnai are herein discussed. Listrura depinnai, especie nova, e descrita de uma pequena area alagada pertencente ao sistema da Laguna dos Patos, Mun...

The species of the genus Trichomycterus inhabiting the laguna dos Patos system are reviewed and five species are recognized. Trichomycterus tropeiro Ferrer & Malabarba has a restricted range and is endemic to the uppermost portion of the rio das Antas. Trichomycterus balios, n. sp., is distributed in the upper portion of the rio das Antas and rio Caí basins. Trichomycterus diatropoporos, n. sp., is endemic to the rio da Prata basin, a tributary of the rio das Antas. Trichomycterus poikilos, n. sp., is widely distributed in the upper portion of the rio Jacuí basin and tributaries of the rio Taquari-Antas. Trichomycterus brachykechenos, n. sp., is endemic to the upper portion of the rio dos Sinos. The new species are distinguishable from most congeners, except for T. davisi, T. mboycy, T. naipi, T. payaya, T. papilliferus, T. perkos, T. plumbeus, and T. tropeiro by the lower number of pectoral-fin rays (I+5-6) and by the first pectoral-fin ray not prolonged as a filament. Other characters distinguish the new taxa from these eight species. The distribution of the genus in the laguna dos Patos system is discussed and a taxonomic key is provided. O gênero Trichomycterus é revisado no sistema da laguna dos Patos e cinco espécies são reconhecidas. Trichomycterus tropeiro Ferrer & Malabarba tem distribuição restrita, ocorrendo somente na porção mais superior do rio das Antas. Trichomycterus balios, sp. n., distribui-se na porção superior das bacias dos rios das Antas e Caí. Trichomycterus diatropoporos, sp. n., é endêmica da bacia do rio da Prata, tributário do rio das Antas. Trichomycterus poikilos, sp. n., é amplamente distribuída nos cursos superiores da bacia do rio Jacuí e tributários dos rios Taquari-Antas. Trichomycterus brachykechenos, sp. n., é endêmica do curso superior do rio dos Sinos. As espécies novas distinguem-se de grande parte de seus congêneres pelo baixo número de raios na nadadeira peitoral (I+5-6) e o primeiro raio da nadadeira peitoral não prolongado como filamento, exceto de T. davisi, T. mboycy, T. naipi, T. papilliferus, T. payaya, T. perkos, T. plumbeus e T. tropeiro, distinguindo-se destas por outros caracteres. A distribuição do gênero no sistema da laguna dos Patos é discutida e uma chave taxonômica é fornecida

A monofilia do gênero Scleronema (Siluriformes: Trichomycteridae), sua posição taxonômica dentre os tricomicterídeos e as relações internas são investigadas através de uma análise integrada de dados morfológicos e moleculares. Uma análise filogenética de evidência total incluindo nove espécies de Scleronema como grupo interno (três nominais e seis reconhecidas como novas) e 24 espécies como grupo externo contemplando todas as subfamílias de Trichomycteridae foi realizada com base em 192 caracteres morfológicos e 2728 caracteres moleculares. Os resultados suportam o monofilia do gênero Scleronema e suas espécies estão agrupadas em dois clados irmãos, grupo Scleronema operculatum e grupo Scleronema minutum, diagnosticáveis através de caracteres da morfologia externa, osteologia e padrão de coloração. O grupo Scleronema operculatum é composto por Scleronema operculatum e uma espécie nova proposta e descrita. O grupo Scleronema minutum compreende Scleronema angustirostre, S. minutum e seis espécies novas reconhecidas, cinco delas descritas aqui. A monofilia de todas as subfamílias de Trichomycteridae foram recuperadas com exceção de Trichomycterinae. A afinidade do gênero Scleronema com os membros das subfamílias Glanapteryginae, Sarcoglanidinae, Stegophilinae, Tridentinae e Vandelliinae é corroborada e discutida. The monophyly of the genus Scleronema (Siluriformes: Trichomycteridae), its taxonomic position and the internal relationships are investigated through an integrated analysis of morphological and molecular data. A total evidence phylogenetic analysis including nine species of Scleronema in the ingroup (three nominal species plus six recognized as new), and 24 species as outgroup, including all subfamilies of Trichomycteridae, was performed on the basis of 192 morphological and 2728 molecular characters. The results support the monophyly of the genus Scleronema. Its species are grouped into two sister clades, the Scleronema operculatum group and the Scleronema minutum group, diagnosed by characters of external morphology, osteology and color pattern. The Scleronema operculatum group consists of Scleronema operculatum and one new species described here. The Scleronema minutum group comprises Scleronema angustirostre, S. minutum and six new species, five described herein. The monophyly of all subfamilies of Trichomycteridae were recovered except for Trichomycterinae. The affinity of the genus Scleronema with members of the subfamilies Glanapteryginae, Sarcoglanidinae, Stegophilinae, Tridentinae and Vandelliinae is supported and discussed.

Ituglanis boitata, new species, is described from the rio Tramandaí system and rio Mampituba and Araranguá basins, southern Brazil. This new species is distinguished from congeners with the exception of I. bambui, I. boticario, I. paraguassuensis and I. proops by the supraorbital canal of the cephalic laterosensory system interrupted between nasal and frontal sections and the presence of pore s2 (vs. supraorbital canal uninterrupted and pore s2 absent). Ituglanis boitata differs from these species in osteological characters, measurements and body coloration. Ituglanis boitata presents a noticeable endemism in the Tramandaí-Mampituba freshwater ecoregion, a recognized biogeographic unit for freshwater fishes including other 22 endemic species. A discussion about the intraspecific variation in the cephalic laterosensory system within Trichomycterinae is also provided.

A new species assigned to the genus Trichomycterus from the area of the waterfalls of Tabay stream, Paraná River basin, Misiones, Argentina, is described. Trichomycterus ytororo sp. nov. is distinguished from all other species in the genus by the presence of 31?35 dorsal procurrent caudal-fin rays and the combination of some external characters such as: coloration, number of pectoral?fin rays and pores of the laterosensory canals. The new taxon belongs to a presumably monophyletic group of species composed of T. crassicaudatus, T. igobi, and T. stawiarski based on the presence of 24 or more thickly ossified and rigid procurrent caudal-fin rays with a slender distal tip extending along the tips of at least ten neural spines. Fil: Teran, Guillermo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo. San Miguel de Tucumán; Argentina Fil: Ferrer, Juliano. Universidade Federal do Rio Grande do Sul; Brasil Fil: Benitez, Mauricio Fabián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; Argentina Fil: Alonso, Felipe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentina Fil: Aguilera, Gaston. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo. San Miguel de Tucumán; Argentina Fil: Mirande, Juan Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo. San Miguel de Tucumán; Argentina

Os ambientes aquáticos da Bacia do rio Taquari-Antas (Bacia da Laguna dos Patos, sul do Brasil) vêm sofrendo considerável transformação, principalmente em razão da implantação de barragens para geração de energia elétrica. Com o objetivo de estabelecer um diagnóstico amplo da ictiofauna da Bacia do Taquari-Antas, realizou-se um inventário das espécies dessa bacia a partir de dados primários e secundários. Foram obtidos 5.299 registros válidos de espécies de peixe na bacia, representando 119 espécies e 519 localidades amostradas. Ocorrem, na bacia, 13 espécies não nativas, seis das quais são oriundas de outras bacias neotropicais. Cerca de 24% de todas as espécies carecem de descrição taxonômica no nível específico. Foram registradas três espécies nativas migradoras de longa distância (Leporinus obtusidens, Prochilodus lineatus e Salminus brasiliensis) e duas potenciais migradoras de média distância (Parapimelodus nigribarbis e Pimelodus pintado). O fato de uma espécie ser oficialmente reconhecida como ameaçada na bacia (S. brasiliensis) e a grande proporção de espécies de distribuição restrita (21,7% do total) devem ser levados em consideração nos esforços de conservação. The aquatic habitats of the Taquari-Antas river basin (in the Patos Lagoon basin, southern Brazil) are under marked environmental transformation because of river damming for hydropower production. In order to provide an information baseline on the fish fauna of the Taquari-Antas basin, we provide a comprehensive survey of fish species based on primary and secondary data. We found 5,299 valid records of fish species in the basin, representing 119 species and 519 sampling sites. There are 13 non-native species, six of which are native to other Neotropical river basins. About 24% of the total native species are still lacking a taxonomic description at the species level. Three native long-distance migratory species were recorded (Leporinus obtusidens, Prochilodus lineatus, Salminus brasiliensis), as well as two potential mid-distance migrators (Parapimelodus nigribarbis and Pimelodus pintado). Although there is only one officially endangered species in the basin (S. brasiliensis), restricted range species (21.7% of total species) should be considered in conservation efforts.

O gênero Trichomycterus é revisado no sistema da laguna dos Patos e cinco espécies são reconhecidas. Trichomycterus tropeiro Ferrer & Malabarba tem distribuição restrita, ocorrendo somente na porção mais superior do rio das Antas. Trichomycterus balios, sp. n., distribui-se na porção superior das bacias dos rios das Antas e Caí. Trichomycterus diatropoporos, sp. n., é endêmica da bacia do rio da Prata, tributário do rio das Antas. Trichomycterus poikilos, sp. n., é amplamente distribuída nos cursos superiores da bacia do rio Jacuí e tributários dos rios Taquari-Antas. Trichomycterus brachykechenos, sp. n., é endêmica do curso superior do rio dos Sinos. As espécies novas distinguem-se de grande parte de seus congêneres pelo baixo número de raios na nadadeira peitoral (I+5-6) e o primeiro raio da nadadeira peitoral não prolongado como filamento, exceto de T. davisi, T. mboycy, T. naipi, T. papilliferus, T. payaya, T. perkos, T. plumbeus e T. tropeiro, distinguindo-se destas por outros caracteres. A distribuição do gênero no sistema da laguna dos Patos é discutida e uma chave taxonômica é fornecida. The species of the genus Trichomycterus inhabiting the laguna dos Patos system are reviewed and five species are recognized. Trichomycterus tropeiro Ferrer & Malabarba has a restricted range and is endemic to the uppermost portion of the rio das Antas. Trichomycterus balios, n. sp., is distributed in the upper portion of the rio das Antas and rio Caí basins. Trichomycterus diatropoporos, n. sp., is endemic to the rio da Prata basin, a tributary of the rio das Antas. Trichomycterus poikilos, n. sp., is widely distributed in the upper portion of the rio Jacuí basin and tributaries of the rio Taquari-Antas. Trichomycterus brachykechenos, n. sp., is endemic to the upper portion of the rio dos Sinos. The new species are distinguishable from most congeners, except for T. davisi, T. mboycy, T. naipi, T. payaya, T. papilliferus, T. perkos, T. plumbeus, and T. tropeiro by the lower number of pectoral-fin rays (I+5-6) and by the first pectoral-fin ray not prolonged as a filament. Other characters distinguish the new taxa from these eight species. The distribution of the genus in the laguna dos Patos system is discussed and a taxonomic key is provided.

O gênero Trichomycterus é revisado no sistema da laguna dos Patos e cinco espécies novas são reconhecidas. Trichomycterus tropeiro Ferrer & Malabarba tem distribuição restrita, ocorrendo somente na porção mais superior do rio das Antas. Trichomycterus sp. n. A distribui-se na porção superior das bacias dos rios das Antas e Caí. Trichomycterus sp. n. B é endêmica da bacia do rio da Prata, tributário do rio das Antas. Trichomycterus sp. n. C é amplamente distribuída nos cursos superiores da bacia do rio Jacuí e tributários do rio Taquari-Antas. Trichomycterus sp. n. D é endêmica do curso superior do rio do Sinos. As novas espécies distinguem-se de grande parte de seus congêneres do sul e sudeste do Brasil pelo baixo número de raios na nadadeira peitoral (I+5-6) e o primeiro raio da nadadeira peitoral não prolongado como filamento, exceto T. davisi, T. mboycy, T. naipi, T. papilliferus, T. plumbeus e T. tropeiro, distinguindo-se destas por outros caracteres. The genus Trichomycterus from laguna dos Patos system is reviewed and five species are recognized. Trichomycterus tropeiro Ferrer & Malabarba has a restricted range and is endemic from the uppermost portion of the rio das Antas. Trichomycterus sp. n. A is distributed in upper portion of rio das Antas and rio Caí basins. Trichomycterus sp. n. B is endemic from rio da Prata basin, tributary of rio das Antas. Trichomycterus sp. n. C is widely distributed in upper portion of rio Jacuí basin and tributaries of rio Taquari- Antas. Trichomycterus sp. n. D is endemic from upper portion of rio dos Sinos. The new species are distinguishable from most congeners in the southeast and southern Brazil, except from T. davisi, T. mboycy, T. naipi, T. papilliferus, T. plumbeus, and T. tropeiro by the lower number of pectoral-fin rays (I+5-6) and by the first pelvic-fin ray not prolonged as filament. Others characters distinguish the new taxa from these six species.

Trichomycterus tropeiro, new species, is described from the headwaters of the rio das Antas, laguna dos Patos system, Southern Brazil. Trichomycterus tropeiro is distinguishable from other species of the genus by the absence of pelvic fins and pelvic girdle, except from Trichomycterus candidus and Trichomycterus catamarcensis. It differs from these two species in several counts and measurements. The apparent endemism of the species is discussed.

Austrolebias paucisquama, uma nova espécie de peixe anual é descrita da bacia do rio Vacacaí, tributário do rio Jacuí, Rio Grande do Sul, Brasil. A nova espécie pertence ao grupo Austrolebias alexandri, que apresenta duas apomorfias, pontos azuis claros e nadadeiras peitorais cinza escuro nos machos. Distingue-se das outras espécies do grupo pelo reduzido número de escamas ao redor do pedúnculo caudal (12) e pelo menor número de raios na nadadeira dorsal dos machos (17-21). A ausência de órgãos de contato na superfície interior das nadadeiras peitorais nos machos e o padrão de colorido das fêmeas – flancos marrom claro com variável número de pontos pretos relativamente alongados distribuídos principalmente na porção posterior – distinguem A. paucisquama das outras espécies do gênero. Austrolebias paucisquama is described from the rio Vacacaí drainage, a tributary to the rio Jacuí, Rio Grande do Sul, Brazil. The new species belongs to the Austrolebias alexandri species-group, by sharing the apomorphic bright blue iridescence and dark gray pectoral fins in males. It is distinguished from other species of this group by having fewer scales around caudal peduncle (12) and fewer dorsal-fin rays in males (17-21). The lack of contact organs on the inner surface of the pectoral fin in males and the color pattern of females – ground color light brownish, sides of body with a variable number of relatively large dark black spots distributed mostly on posterior portion of body – distinguish A. paucisquama from all other species of the genus.

Ituglanis boitata , new species, is described from the rio Tramandai system and rio Mampituba and Ararangua basins, southern Brazil. This new species is distinguished from congeners with the exception of I. bambui , I. boticario , I. paraguassuensis and I. proops by the supraorbital canal of the cephalic laterosensory system interrupted between nasal and frontal sections and the presence of pore s2 ( vs. supraorbital canal uninterrupted and pore s2 absent). Ituglanis boitata differs from these species in osteological characters, measurements and body coloration. Ituglanis boitata presents a noticeable endemism in the Tramandai–Mampituba freshwater ecoregion, a recognized biogeographic unit for freshwater fishes including other 22 endemic species. A discussion about the intraspecific variation in the cephalic laterosensory system within Trichomycterinae is also provided.

The genus Trichomycterus is a highly diverse group of Neotropical catfishes that encompass almost 60% of all the cur-rently recognized species of the Trichomycteridae. A new species of this genus, T. perkos, is herein described from tribu-taries of the Paranapanema and Uruguai River basins, southern Brazil. The new species exhibits a remarkable ontogeneticchange in its pigmentation, having a unique color pattern when adult. The adult pigmentation consists of three wide darkbrown stripes, located in an inner skin layer of trunk and caudal peduncle, combined with a superficial light brown freck-led pattern on the dorsum and caudal peduncle. Small, presumably juvenile specimens lack the superficial freckles butalready have the dark stripes, thus resembling the color pattern of a few other congeners. Nevertheless, several unequiv-ocal morphological features distinguish both juveniles and adults of T. perkos from these congeners. In spite of the diffi-culties in estimating phylogenetic relationships within Trichomycterus, the new species is tentatively proposed as being the sister-taxon of a small group of species composed by T. crassicaudatus, T. igobi, and T. stawiarski.

Trichomycterus é um gênero polifilético que contém espécies com complexas histórias taxonômicas. Esta revisão taxonômica está focada nas espécies de Trichomycterus que habitam drenagens costeiras do Sul e Sudeste do Brasil, desde o Sistema do rio Tramandaí (sul) até a bacia do rio Ribeira de Iguape (norte). O objetivo desse estudo é realizar uma revisão taxonômica integrativa do gênero baseado em dados morfológicos e moleculares. Sendo assim, uma nova espécie de Trichomycterus foi descrita para a bacia do rio Ribeira de Iguape a o status taxonômico dos seus congêneres presentes na bacia foram discutidos (cap. 1). Adicionalmente, uma extensiva revisão das espécies de Trichomycterus das drenagens costeiras do Sul e Sudeste do Brasil foi utilizada para avaliar os limites de espécies em uma análise integrativa e discutimos os processos biogeográficos envolvidos na diversificação das espécies de Trichomycterus (cap. 2). Identificamos 12 morfoespécies que habitam as drenagens costeiras do Sul e Sudeste do Brasil baseado em uma combinação de caracteres morfológicos. Confirmamos a presença de seis espécies de Trichomycterus anteriormente citadas para a região (T. davisi, T. cubataonis, T. guaraquessaba, T. jacupiranga, T. tupinamba, and T. zonatus), além de T. alternatus. Reconhecemos também possíveis novas espécies (Trichomycterus sp. ‘ribeira’, Trichomycterus sp. ‘malacara’, Trichomycterus sp. 'tubarão' and T. aff. davisi). Confirmamos a presença de seis espécies de Trichomycterus anteriormente citadas para a região (T. davisi, T. cubataonis, T. guaraquessaba, T. jacupiranga, T. tupinamba, and T. zonatus), além de T. alternatus. Reconhecemos também possíveis novas espécies (Trichomycterus sp. ‘ribeira’, Trichomycterus sp. ‘malacara’, Trichomycterus sp. 'tubarão' and T. aff. davisi). Confirmamos a ampla distribuição de T. balios tanto do Sistema da Laguna dos Patos (localidade tipo), bacia do rio Uruguay e drenagens costeiras das bacias dos rios Mampituba e Itajaí. Finalmente, sugerimos que a diversificação em Trichomycterus do Sul e Sudeste do Brasil parece estar associada a ambos os eventos de troca de fauna, primariamente com trocas de fauna ocorridas entre drenagens costeiras e continentais e secundariamente restritas as paleodrenagens na plataforma continental. Trichomycterus is a systematic puzzle, highly diverse and contains species with complexes taxonomic histories. This taxonomic review is focused on coastal drainages of South and Southeast Brazil from Tramandaí River System (south) to the Ribeira de Iguape River basin (north). The aim is to provide an integrative taxonomic revision of the genus based on morphological and molecular data. Thus, a new species of Trichomycterus was described for Ribeira de Iguape River basin and the taxonomic status of the remaining congeners in the basin is discussed (chapter 1). In addition, an extensive review of species of Trichomycterus from coastal drainages of South and Southeastern Brazil was used to evaluate species limit in an integrative analysis, and we discussed the biogeographic processes involved in the recent diversification of Trichomycterus species (chapter 2). We identified 12 morphospecies inhabiting coastal drainages of South and Southeast Brazil based on a combination of morphological characters. We confirmed the presence of six species of Trichomycterus previously cited for the region (T. davisi, T. cubataonis, T. guaraquessaba, T. jacupiranga, T. tupinamba, and T. zonatus) in addition to T. alternatus. We also recognized the putative new species (Trichomycterus sp. ‘ribeira’, Trichomycterus sp. ‘malacara’, Trichomycterus sp. 'tubarão' and T. aff. davisi. We confirmed the widely distributed of T. balios through Laguna dos Patos System (type-locality), Uruguay River basin and two coastal drainages the Mampituba and the Itajaí river basins. Finally, we suggest that the diversification in Trichomycterus from South and Southeast Brazil seem to be associated with both events of exchange of fauna, in primary instances with faunal exchanges occurred between coastal and continental drainages and as secondary distributions are contrained by paleodrainage configuration in the atlantic continental shelf.