A new species of Parotocinclus from the upper Rio Paraguaçu, Bahia, Brazil, is described. The new species is distinguished from all congeners by its unique color pattern, with irregular dark blotches ...resulting in a somewhat marble-spotted pattern on head and trunk of most specimens and dorsum of head with a conspicuous V-shaped light mark from tip of snout to nares. The new species is also distinguished from congeners by having the lower lip elongated posteriorly and reaching or surpassing the anterior margin of cleithrum on the pectoral girdle, the canal cheek plate on the ventral surface of the head reduced and with a slightly concave margin, and abdomen covered by small embedded platelets, without contact with each other and not arranged in a line between the pectoral-fin axilla and pelvic-fin origin. The presence of a thick and rough skin in the interradial membrane of pelvic fin exclusively in the females of P. nandae is reported by the first time to occurs in Siluriformes.
Abstract The Northeastern Mata Atlântica freshwater ecoregion (NMAF) is recognized for the high degree of endemism of its ichthyofauna, whose evolutionary and biogeographic histories are still poorly ...understood. Oligosarcus acutirostris is a freshwater fish species endemic to the NMAF, which is distributed in coastal rivers and streams draining Bahia, Espírito Santo, and part of Minas Gerais states in eastern Brazil. Its widespread distribution in currently isolated river basins along the NMAF prompted this study, which aimed to understand what scenarios would be involved in determining its current distribution pattern, and to contribute to a better understanding of the biogeographic history of the NMAF. For this, mitochondrial and nuclear DNA sequences were analyzed based on samples from different localities along the species distribution, including its type locality. Overall, phylogeographic analyses indicate a strong genetic structure within the species evidenced mainly by the non-sharing of haplotypes between most of the basins analyzed. According to the AMOVA results, the current distribution of haplotypes is better explained by the Pleistocene coastal paleodrainages. The results are also used to test and complement a biogeographic hypothesis previously proposed for the drainages of the NMAF.
Resumo A ecorregião de água doce Mata Atlântica Nordeste (NMAF) é reconhecida pelo alto grau de endemismo da sua ictiofauna, cujas histórias evolutiva e biogeográfica ainda são pouco compreendidas. Oligosarcus acutirostris é uma espécie de peixe de água doce endêmica da NMAF, que está distribuída em rios e riachos costeiros que drenam os estados da Bahia, Espírito Santo e parte de Minas Gerais, no leste do Brasil. Sua ampla distribuição em bacias atualmente isoladas ao longo da NMAF motivou este estudo, que teve como objetivos entender quais cenários estariam envolvidos na determinação do seu padrão atual de distribuição e contribuir para uma melhor compreensão da história biogeográfica da NMAF. Para isto, foram analisadas sequências de DNA nuclear e mitocondrial, a partir de amostras de diferentes localidades ao longo da distribuição da espécie, incluindo sua localidade tipo. No geral, as análises filogeográficas indicam forte estruturação genética na espécie, evidenciada principalmente pelo não compartilhamento de haplótipos entre a maioria das bacias analisadas. De acordo com os resultados da AMOVA, a distribuição atual dos haplótipos é melhor explicada pelas paleodrenagens costeiras do Pleistoceno. Os resultados obtidos também são utilizados para testar e complementar hipótese biogeográfica previamente proposta para as drenagens da NMAF.
The current distribution of freshwater fishes across multiple basins along Eastern Brazil can be associated to two main events: river captures or temporary paleoconnections. Apparently, river ...captures had a more significant role on distribution and structuring of species from upland areas, such as Glandulocauda melanopleura. Populations of this species are found in contiguous drainages in presently isolated upper parts of Rio Tietê and the coastal basins of Guaratuba, Itatinga, Itanháem, and Ribeira de Iguape, in the Atlantic Forest domain. The allopatric and disjoint distribution of G. melanopleura associated with variation of morphological characters detected among geographically isolated populations stimulated this study. Thus, an integrative approach was undertaken, including morphological and molecular data, to better understand the evolutionary history of the species and the area where it occurs. Molecular analyses based on two mitochondrial markers revealed a strong genetic structure within G. melanopleura, that allowed recognition of two lineages, one distributed in both the upper Tietê and Itanhaém and the other in the Guaratuba. Overall, morphological data revealed some intraspecific overlapping variation, indicating that all samples are conspecific. Phylogenetic and phylogeographic analyses allied to divergence times and geomorphological information indicate that the current distribution of G. melanopleura is a result of relatively recent river captures involving the Tietê and some other coastal drainages. Although of recent origin, they occurred long enough to completely isolate these populations, since there are no haplotypes sharing between them. The conservation status of this species is also discussed, and our results corroborate the need to understand population structure for conservation planning.
The Northeastern Mata Atlântica freshwater ecoregion (NMAF) includes part of the eastern Brazilian coastal drainages, has high level of fish endemism and great biogeographic significance. A taxonomic ...inventory of freshwater fishes from 25 drainages of the NMAF ecoregion and a biogeographic analysis using the Parsimony Analysis of Endemicity (PAE) method were carried out. A total of 192 native species was listed. The PAE method was applied to 24 basins and 37 species, resulting in five equally parsimonious area diagrams. The strict consensus diagram indicates the existence of two main groups of basins throughout the NMAF ecoregion. These groups were denominated: North Group and Central-South Group. The Central-South Group shows a basal polytomy composed by two Groups (Central Group and South Group) plus the rio Itapemirim basin. The North Group is composed by eight drainages from the rio Sergipe to the rio Paraguaçu, the Central Group by five drainages from the rio Cachoeira to the rio Jequitinhonha, and the South Group by nine drainages from the rio Buranhém to the rio Doce. Comments about the species distribution and the fish fauna shared with adjacent ecoregions are provided. We also present a comparison of the hypothesis of river relationships proposed herein with published phylogenetic hypotheses that include taxa relevant to this study.
A ecorregião Mata Atlântica Nordeste (NMAF) inclui parte das drenagens costeiras do leste do Brasil, tem alto grau de endemismo de peixes e grande significado biogeográfico. Um levantamento taxonômico da ictiofauna de água doce de 25 drenagens da ecorregião NMAF e uma análise biogeográfica utilizando o método de Análise de Parcimônia de Endemismo (PAE) foram realizados. Um total de 192 espécies nativas foi listado. O método PAE foi aplicado a 24 bacias e 37 espécies, resultando em cinco diagramas de áreas igualmente parcimoniosos. O diagrama de consenso estrito indica a existência de dois grupos de bacias principais ao longo da ecorregião NMAF. Estes grupos foram denominados: Grupo Norte e Grupo Centro-Sul. O Grupo Centro-Sul apresenta uma politomia basal composta por dois grupos (Grupo Centro e Grupo Sul) mais a bacia do rio Itapemirim. O Grupo Norte é formado por oito drenagens entre o rio Sergipe e o rio Paraguaçu, o Grupo Centro por cinco drenagens entre o rio Cachoeira e o rio Jequitinhonha e o Grupo Sul por nove drenagens entre o rio Buranhém e rio Doce. Comentários sobre a distribuição das espécies e a fauna compartilhada com ecorregiões adjacentes são fornecidos. Apresentamos também uma comparação da hipótese de relação aqui obtida com filogenias publicadas para alguns táxons relevantes ao presente estudo.
Two new species of Characidium, one from the rio Pardo basin, and anotherfrom the rio Paraguaçu basin, Bahia, Brazil, are described. The first new speciesis distinguished from its congeners by having ...conspicuous black vertical traces on body, formed by the concentration of melanophores along posterior margin of scales. The species further differs from most congeners by the presence of a conspicuous 3-shaped black blotch on the caudal fin and isthmus not covered by scales. The other new species is distinguished from congeners by having irregular dark blotches on dorsum alternating elongation to one or the other side of body, usually not connected to lateral blotches. The species can be further characterized by the absence of conspicuous blotches or bars on fins and the presence of secondary sexual dimorphism, such as pelvic fins of mature males longer than in females and with bony hooks.
Abstract Neotropical Ichthyology promotes the Special Issue (SI) “Human impacts and the loss of Neotropical freshwater fish diversity” with the purpose of publishing relevant scientific articles on ...the current biodiversity crisis and the loss of Neotropical freshwater fishes in the Anthropocene. The SI is composed of 22 publications, being two review articles and 20 original articles. A total of 107 researchers contributed to these papers, involving 44 institutions based in Brazil and six other countries. Published articles investigated main anthropic activities and their impacts on fish diversity, with special focus on river regulation, mining, land use changes, aquaculture, and fisheries. Studies provided evidence about the loss of fish diversity in the Neotropics, including fish kill events, demographic changes, contamination, changes in assemblage structure, loss of taxonomic and functional diversity, besides the degradation of ecosystem functions and services, and the lack of effective protection and conservation. Studies were conducted in rivers, streams, lakes, and reservoirs from different Neotropical systems. The studies published in this SI represent a relevant sample of the current worrisome situation of freshwater fishes in the Neotropical region and call for urgent revision in environmental policies, management and conservation initiatives, and socioeconomic priorities.
Resumo A revista Neotropical Ichthyology lança o Volume Especial (SI) “Human impacts and the loss of Neotropical freshwater fish diversity” com o objetivo de publicar artigos científicos relevantes sobre a atual crise da biodiversidade e a perda de diversidade de peixes de água doce Neotropicais no Antropoceno. O SI é composto por 22 publicações, sendo dois artigos de revisão e 20 artigos originais. Um total de 107 pesquisadores contribuíram com esses artigos, envolvendo 44 instituições sediadas no Brasil e em seis outros países. Os artigos publicados investigaram as principais atividades antrópicas e seus impactos sobre a diversidade de peixes, com foco especial na regulação dos rios, mineração, mudanças no uso do solo, aquicultura e pesca. Os estudos forneceram evidências sobre a perda de diversidade de peixes na região Neotropical, incluindo eventos de mortandade, alterações demográficas, contaminação, mudanças na estrutura das assembleias, perda de diversidade taxonômica e funcional, além da degradação de funções e serviços ecossistêmicos, e falta de ações efetivas de proteção e conservação. Os estudos foram conduzidos em rios, riachos, lagos e reservatórios de diferentes sistemas Neotropicais. Os estudos publicados neste SI representam uma amostra relevante da atual situação dos peixes de água doce na região Neotropical, reforçando a necessidade de revisão das políticas ambientais, ações de manejo e conservação, e prioridades socioeconômicas.
Characidium samurai, a species of the family Crenuchidae apparently endemic to rio das Almas and rio Vermelho basins, Bahia, Brazil, is described. The new species is readily distinguishable from its ...congeners, except C. lanei, by having a dark lateral band along the head and body that is particularly broad from the rear of the head to the end of the caudal peduncle (1.5 or 2 scales wide) and by the absence of dark bars or blotches on the ventral half of the body. Characidium samurai differs from C. laneiby having the lateral band with straight borders overall (vs.lateral band with somewhat irregular borders due to blotches extending dorsally or ventrally), anal fin ii,7-8 (vs. ii,6), and 4 horizontal scale rows above the lateral line and 4 below (vs. 5/3). It further differs from congeners by a series of features, including isthmus completely covered by scales, lateral line complete with 34-37 perforated scales, 9 scales on the transversal line, 14 scale rows around the caudal peduncle, anal fin ii,7-8, and the absence of dark bars or spots on the fins, except by a faded dorsal-fin bar. The presence of pseudotympanum in four species of Characidium is discussed.
ABSTRACT A new species of Astyanax from tributaries of the rio de Contas, Bahia, Brazil, is described. The new species differs from congeners by having three horizontal series of scales from lateral ...line to pelvic-fin origin and the distal margin of third infraorbital distinctly separated from vertical and horizontal limbs of preopercle, leaving a broad area not covered by superficial bones. The new species further differs from most congeners by the presence of bony hooks on all fins of mature males. Particularly from congeners occurring in rivers of the Northeastern Mata Atlântica freshwater ecoregion, it further differs by having the highest body depth just anterior to the dorsal-fin origin, 34-37 pored lateral line scales, a vertically elongated conspicuous dark humeral blotch reaching below the lateral line and a conspicuous dark wide midlateral stripe extending from the clear area on the rear of the humeral blotch to the end of middle caudal-fin rays and forming an inconspicuous blotch on caudal peduncle.
RESUMO Uma espécie nova de Astyanax de tributários do rio de Contas, Bahia, Brasil, é descrita. A espécie nova difere das congêneres por ter três séries horizontais de escamas entre a linha lateral e a origem da nadadeira pélvica e margem distal do terceiro infraorbital distintamente separada dos ramos vertical e horizontal do pré-opérculo, deixando uma ampla área sem ossos superficiais. A espécie nova difere, ainda, da maioria das congêneres pela presença de ganchos ósseos em todas as nadadeiras de machos maduros. Particularmente das congêneres que ocorrem nas drenagens da Ecorregião Mata Atlântica Nordeste, difere ainda por ter a maior altura do corpo imediatamente anterior à origem da nadadeira dorsal, 34-37 escamas perfuradas na linha lateral, presença de uma mancha umeral conspícua, verticalmente alongada, ultrapassando ventralmente a linha lateral e uma faixa escura mediana lateral larga, estendendo-se da área clara após a mancha umeral até o fim dos raios medianos caudais e formando uma mancha inconspícua no pedúnculo caudal.
ABSTRACT Although former studies on systematics and biogeography represent a progress on the knowledge of the tribe Glandulocaudini, none was grounded on molecular evidence. Thus, the first ...hypothesis of relationships for the tribe based on a multilocus analysis is presented, including all genera and most of the valid species. DNA sequences of Glandulocauda caerulea and Mimagoniates sylvicola were analyzed for the first time. A molecular clock analysis was used to estimate the origin of the Glandulocaudini and the approximate timing of cladogenetic events within the group. Glandulocaudini was recovered as monophyletic. No hypothesis recovered Glandulocauda as monophyletic, since G. melanopleura is sister to Lophiobrycon weitzmani while G. caerulea is closely related to Mimagoniates. The relationships within the latter genus were resolved. The molecular clock results indicate the origin of the Glandulocaudini during the Miocene with diversification in the group occurring from Neogene to Pleistocene. These results corroborated the hypothesis that its origin took place on the Brazilian crystalline shield with the subsequent occupation of the Atlantic Coastal drainages. Apparently, Pleistocene sea-level fluctuations might have shaped the distribution pattern of some species in Glandulocaudini.
RESUMO Embora estudos prévios sobre sistemática e biogeografia representam um avanço no conhecimento da tribo Glandulocaudini, nenhum foi baseado em evidência molecular. Assim, a primeira hipótese de relações para a tribo com base em uma análise multilocus é apresentada, incluindo todos os gêneros e a maioria das espécies válidas. Sequências de DNA de Glandulocauda caerulea e Mimagoniates sylvicola foram analisadas pela primeira vez. Uma análise de relógio molecular foi utilizada para estimar a origem de Glandulocaudini e datas aproximadas de eventos cladogenéticos dentro do grupo. Glandulocaudini foi recuperada como monofilética. Nenhuma hipótese recuperou Glandulocauda como monofilético, uma vez que G. melanopleura é irmã de Lophiobrycon weitzmani e G. caerulea está proximamente relacionada a Mimagoniates. As relações dentro deste último gênero foram resolvidas. Os resultados do relógio molecular indicam que Glandulocaudini originou-se durante o Mioceno, com diversificação dentro do grupo ocorrendo desde o Neogeno até o Pleistoceno. Estes resultados corroboram a hipótese da sua origem no escudo cristalino brasileiro, com a subsequente ocupação das drenagens costeiras atlânticas. Aparentemente, as flutuações pleistocênicas do nível do mar podem ter moldado o padrão de distribuição de algumas espécies em Glandulocaudini.
The following letter, from a network of women zoologists, is a reply to the article of AlShebli et al. (2020), which suggests that female protégés reap more benefits when mentored by men and ...concludes that female mentors hinder the success of their female protégés and the quality of their impact. This contribution has two parts. First, we highlight the most relevant methodological flaws which, in our opinion, may have impacted the conclusions of AlShebli et al. (2020). Second, we discuss issues pertaining to women in science, bring a perspective of Women in Zoology and discuss how current diversity policies are positively changing our field.
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