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Rays of the superorder Batoidea comprise the most diverse group of chondrichthyans in terms of valid species and morphological disparity. Up to the present little agreement is observed in studies based on morphological and molecular data focused on uncovering the interrelationships within Batoidea. Morphology-based phylogenies of batoids have not included characters related to the afferent branchial arteries, and little is known about the variation in this anatomical complex in rays. Herein, representatives of 32 genera from 19 families currently recognized of rays were examined as well as some shark taxa. Seven new characters are proposed and tested in two different analyses, one on their own and in the other they were added to the morphological data matrix of the most recent analysis of interrelationships within Batoidea. The arrangement of afferent branchial arteries differs mainly among orders and families of batoids. The absence of a common trunk from which the three posteriormost afferent arteries branch is interpreted as a synapomorphy for Myliobatiformes and the presence of a coronary cranial artery as an autapomorphy for Mobula hypostoma. A close spatial relationship between the second and third afferent arteries within the common branch from the ventral aorta is proposed as a synapomorphy for Rajiformes with a secondary modification in Sympterygia. Data about patterns in afferent branchial arteries in additional taxa such as Squaliformes and Chimaeriformes are needed to better understand the evolution of this character complex among chondrichthyans.

The definition and scope of the genus Carcharhinus has undergone several changes over the years and recent molecular studies have questioned its monophyly by the inclusion of other carcharhinid genera. Although many descriptions of chondrocranium are available for Carcharhinus species, some inconsistences and divergences are found in the literature, mainly regarding the foramina of the orbital region. In this study, the chondrocranium of the silky shark, Carcharhinus falciformis, from specimens caught at the Brazilian coast and the terminology of its components is revised has been described. Chondrocrania of other Carcharhinus species and carcharhinid genera are also examined in order to investigate the phylogenetic significance of chondrocranial morphology. Three new anatomical terms and nine chondrocrania characters are proposed and described in detail. The chondrocranial morphology varies widely among Carcharhinus species mainly regarding the rostrum and nasal capsules. The chondrocrania of Prionace, Nasolamia, and Negaprion are similar to Carcharhinus species and reveal the need to further explore the relationships among these genera. Characters potentially informative for systematics are the shape of rostral node, the preorbital process, and the subethmoidal fossa, and the occurrence of an epiphyseal notch and foramen, and must be included in phylogenetic studies encompassing other carcharhiniforms.

The scapulocoracoid morphology in batoids has been investigated by previous authors but descriptions and illustrations of its ventral surface are lacking for Riorajini species. Here, we describe and illustrate the lateral and ventral views of the scapulocoracoid in females and males of Rioraja agassizi and Atlantoraja species, and six new measurements are proposed. In adult females, the distance between procondyles, distance between metacondyles, width of the coracoid bar, distance between mesocondyle and metacondyle, and the first posterior ventral foramen width are proportionally wider than in males. In juveniles of the four species, differences between sexes regarding proportional dimensions are less conspicuous. The wider and long scapulocoracoid of females may provide more space and protection for the development of embryos but further investigation is needed. Given the influence of sexual dimorphism in proportional dimensions and morphology of the scapulocoracoid, characters associated to this structure need to be cautiously analyzed in future phylogenetic studies.

The genus Scyliorhinus is part of the family Scyliorhinidae, the most diverse family of sharks and of the subfamily Scyliorhininae along with Cephaloscyllium and Poroderma. This study reviews the phylogenetic relationships of species of Scyliorhinus in the subfamily Scyliorhininae. Specimens of all Scyliorhinus species were examined as well as specimens of four of the 18 species of Cephaloscyllium, two species of Poroderma, representatives of almost all other catshark (scyliorhinid) genera and one proscylliid (Proscyllium habereri). A detailed morphological study, including external and internal morphology, morphometry and meristic data, was performed. From this study, a total of 84 morphological characters were compiled into a data matrix. Parsimony analysis was employed to generate hypotheses of phylogenetic relationships using the TNT 1.1. Proscyllium habereri was used to root the cladogram. The phylogenetic analysis, based on implied weighting (k = 3; 300 replications and 100 trees saved per replication), resulted in three equally most parsimonious cladograms with 233 steps, with a CI of 0.37 and an RI of 0.69. The monophyly of the subfamily Scyliorhininae is supported as well as of the genus Scyliorhinus, which is proposed to be the sister group of Cephaloscyllium. The phylogenetic relationships amongst Scyliorhinus species are presented for the first time.

Rioraja agassizii belongs to the monotypic genus Rioraja and differs from the other Riorajini species of the genus Atlantoraja by the shape of anterior nasal flap, squamation, clasper skeleton, body measurements and color pattern. Although R. agassizii is a well-known species, commonly captured in inshore waters of the southwestern Atlantic, its external morphology and internal anatomy have never been fully described and little is known on intraspecific variation within the species. Juvenile and adult, male and female specimens were examined, measured and dissected. Herein, we redescribe the species and present detailed descriptions and illustrations of external morphology, neurocranium, jaws, hyoid and gill arches, and pelvic fin and girdle. Additionally, notes on sexual dimorphism and ontogenetic differences in coloration, body and cranial measurements, and dermal denticles are provided. Resumo Rioraja agassizii pertence ao gênero monotípico Rioraja e difere das demais espécies da tribo Riorajini classificadas no gênero Atlantoraja pelo formato da aba nasal anterior, escamas, esqueleto do clásper, medidas corpóreas e padrão de coloração. Embora R. agassizii seja uma espécie bem conhecida, comumente capturada em águas costeiras do Atlântico Sul Ocidental, sua morfologia externa e anatomia interna não foram totalmente descritas e pouco se sabe sobre a variação intraespecífica nesta espécie. Espécimes juvenis, adultos, machos e fêmeas foram examinados, medidos e dissecados. Neste estudo, a espécie é redescrita e descrições detalhadas e ilustrações da morfologia externa, neurocrânio, maxilas, arcos hioide e branquiais, nadadeira e cintura pélvicas são apresentadas. Adicionalmente, notas sobre dimorfismo sexual e variação ontogenética na coloração, medidas corpóreas e craniais, e dentículos dérmicos são fornecidas.

The definition and scope of the genus Carcharhinus has undergone several changes over the years and recent molecular studies have questioned its monophyly by the inclusion of other carcharhinid genera. Although many descriptions of chondrocranium are available for Carcharhinus species, some inconsistences and divergences are found in the literature, mainly regarding the foramina of the orbital region. In this study, the chondrocranium of the silky shark, Carcharhinus falciformis, from specimens caught at the Brazilian coast and the terminology of its components is revised has been described. Chondrocrania of other Carcharhinus species and carcharhinid genera are also examined in order to investigate the phylogenetic significance of chondrocranial morphology. Three new anatomical terms and nine chondrocrania characters are proposed and described in detail. The chondrocranial morphology varies widely among Carcharhinus species mainly regarding the rostrum and nasal capsules. The chondrocrania of Prionace, Nasolamia, and Negaprion are similar to Carcharhinus species and reveal the need to further explore the relationships among these genera. Characters potentially informative for systematics are the shape of rostral node, the preorbital process, and the subethmoidal fossa, and the occurrence of an epiphyseal notch and foramen, and must be included in phylogenetic studies encompassing other carcharhiniforms.

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Teacher training in higher education has been relatively neglected in Brazilian universities because postgraduate programs are mainly focused on the research that students produce. However, these postgraduate students are expected to become the next university and college professors. Herein, we present the experience of the Zoology Summer Course, a university extension course organized by graduate students from the Zoology Graduate Program at the University of São Paulo, Brazil. This course was created aimed to provide graduate students with an opportunity to develop and practice their teaching skills. To understand the influences, motives, and legacy of the CVZOO on its organizers, we developed a questionnaire and evaluated the responses by focusing on elements of academic formation and prospects for a teaching career, using systematic content analysis procedures as parameters. Our results demonstrate the importance of CVZOO as a space of dialogue and interaction for professional teacher training, as well as an opportunity to exchange experiences and build professional identity. The course has also influenced other academic activities such as the organization of scientific events, mentoring experience, and publications. Lastly, we discuss the importance of teacher training in Brazilian graduate programs and propose initiatives to improve the training of future university teachers. Keywords: Graduation; Extension Course; Students; Biodiversity Extensão universitária e formação docente no Brasil: o Curso de Verão em Zoologia Resumo: A formação docente universitária tem sido bastante negligenciada em universidade brasileiras, uma vez que programas de pós-graduação focam majoritariamente na produção acadêmico-científica de seus alunos. No entanto, espera-se que os pós-graduandos sejam a próxima geração de professores universitários. Neste estudo, nós apresentamos a experiência do Curso de Verão em Zoologia da Universidade de São Paulo, Brasil. Este curso foi criado com o objetivo de proporcionar aos estudantes de pós-graduação a oportunidade de desenvolver e praticar suas habilidades para docência. No intuito de entender as influências, motivações e legado do CVZOO em seus organizadores, nós desenvolvemos um questionário e avaliamos as respostas buscando elementos da formação acadêmica e prospecção para a carreira docente, usando procedimentos de análise de conteúdo como parâmetros Os resultados demonstram a importância do CVZOO como um espaço de diálogo e interação com a prática docente bem como uma oportunidade para trocar experiências e construir uma identidade profissional. O curso tem influenciado em outras atividades acadêmicas, tais como organização de eventos científicos, orientação de alunos e publicações. Por fim, este artigo discute a importância da formação docente em programas de pós-graduação no Brasil e propõe algumas iniciativas para melhorar a formação dos futuros professores universitários. Palavras-chave: Pós-Graduação; Curso de Extensão; Estudantes; Biodiversidade

The presence of claspers is one of the main characteristics of the cartilaginous fishes, but its variations across taxa have received limited use in shark systematics and have generally been neglected in descriptions of species. Clasper descriptions are available only for a few catshark species and most of these are focused only in external morphology. Besides that, divergences regarding the identification of some structures persist in the literature emphasizing the need of more encompassing morphological comparative analyses on claspers of scyliorhinids. In this study, claspers structures of almost all catshark genera were examined, described, and illustrated (except Akheilos and Pentanchus) and comments on their phylogenetic significance are provided. Some characters such as degree of development of rhipidions and terminal dermal cover, occurrence, position and size of accessory marginal and terminal cartilages proved to be useful for taxonomic purposes and their significance along carcharhiniforms systematics needs to be further investigated. RESEARCH HIGHLIGHTS: Clasper morphology of catsharks is described and compared and its systematic significance is discussed here. External morphology and skeleton components of claspers vary widely among scyliorhinids and may be useful in phylogenetic analyses.

Intersexual differences in morphometrics were investigated in five species of the catshark genus Scyliorhinus. ANCOVA was used to test 59 measurements, considering capture location and total length as covariates. In all examined species, pelvic-anal distances and pelvic-fin inner margin lengths were greater in males than in females, representing a clear pattern for the genus.

The catshark genus Scyliorhinus belongs to the family Scyliorhinidae, the most diverse family of sharks, and currently presents 16 valid species according to most modern accounts. The long history of taxonomic rearrangements and inaccurate descriptions of many species have contributed to misidentification of specimens and lack of information on the distributional range and diagnostic characters of its species. Species of Scyliorhinus are reviewed and redescribed here, with detailed descriptions on external morphology, neurocranium, claspers, dermal denticles, and tooth morphology provided for the first time for all species. Sixteen species are recognized as valid: Scyliorhinus boa (Goode & Bean, 1896), S. cabofriensis Soares, Gomes & de Carvalho, 2016, S. canicula (Linnaeus, 1758), S. capensis (Müller & Henle, 1838), S. cervigoni Maurin & Bonnet, 1970, S. comoroensis Compagno, 1988, S. duhamelii (Garman, 1913), S. garmani (Fowler, 1934), S. haeckelii (Miranda Ribeiro, 1907), S. hesperius Springer, 1966, S. meadi Springer, 1966, S. retifer (Garman, 1881), S. stellaris (Linnaeus, 1758), S. torazame (Tanaka, 1908), S. torrei Howell-Rivero, 1936, and S. ugoi Soares, Gomes & Gadig, 2015. The main taxonomic decisions herein taken include the resurrection of S. duhamelii (previously a junior synonym of S. canicula) and the synonimization of S. tokubee with S. torazame. Information on geographic distribution was updated for most species, especially for those with wide ranges (S. canicula, S. haeckelii, S. retifer, and S. stellaris).

A new Southwestern Atlantic species of Parmaturus, P. angelae, new species, is described from two specimens captured off Brazil. It is distinguished from congeners by the following characters: origin of the first dorsal fin anterior to pelvic-fin origin, presence of well-developed upper and lower caudal crests of denticles, dorsal fins subequal, lateral denticles teardrop-shaped and lacking lateral cusplets, denticles evenly spaced, proportional dimensions, and vertebral counts. Parmaturus angelae, new species, is the second species of the genus reported from the Atlantic Ocean and only the third species outside of the Indo-West Pacific region. Parmaturus remains rather poorly defined as only two species have been studied anatomically in any detail.

Sharks of the genus Scyliorhinus from the southwestern Atlantic are reviewed; identification problems and taxonomic misinformation given in the literature are rectified. After extensive examination of the external and internal morphology of specimens collected mostly off southeastern and southern Brazil, Scyliorhinus besnardi Springer & Sadowsky, 1970 is placed in the synonymy of S. haeckelii (Miranda Ribeiro, 1907), which is thoroughly redescribed. Additionally, a new species, Scyliorhinus cabofriensis, sp. nov., is described from the state of Rio de Janeiro, distinguished from all southwestern Atlantic congeners by its color pattern, clasper and neurocranial morphology, and proportional measurements. A key to Scyliorhinus species occurring in the southwestern Atlantic is also provided.

A new species of catshark (Carcharhiniformes, Scyliorhinidae), Scyliorhinus ugoi sp. nov., is described from off Northeastern and Southeastern Brazil. The new species is closest to the Scyliorhinus haeckelii/besnardi group and S. hesperius but differs in background coloration, head width, sexual maturity, and in cranial and body proportions.

A new species of catshark (Carcharhiniformes, Scyliorhinidae), Scyliorhinus ugoi sp. nov., is described from off Northeastern and Southeastern Brazil. The new species is closest to the Scyliorhinus haeckelii/besnardi group and S. hesperius but differs in background coloration, head width, sexual maturity, and in cranial and body proportions.