Resumo Esta pesquisa teve como objetivo estimar a relação peso-comprimento (LWR) da arraia Potamotrygon wallacei, conhecida localmente como cururu, que foi capturada em igarapés e lagos na região do médio Rio Negro, Amazonas, Brasil. As arraias foram capturadas durante a noite (das 23h-1h) nas margens dos igarapés e lagos, por meio de busca ativa utilizando canoas de madeira, lanternas de cabeça e puçás. As coletas foram realizadas nos meses de novembro de 2017 (5 dias), fevereiro (8 dias), março (3 dias) e abril (2 dias) de 2018, totalizando 18 dias de amostragem. Foram medidos o peso fresco total com precisão de 0,01 g e a largura do disco com precisão de 0,1 cm. Os parâmetros a e b da equação W= a.DWb foram estimados. Este estudo prover novos dados de comprimento máximo para a arraia cururu.

Abstract This research aimed to estimate the length-weight ratio (LWR) of the stingray Potamotrygon wallacei, known locally as the cururu, which was caught in streams and lakes in the middle Negro River region, Amazonas, Brazil. The stingrays were captured during the night (from 11 pm to 1 am) near the shores of streams and lakes, through active search using wooden canoes, head lanterns and scoop nets. The samplings were carried out in November 2017 (5 days), February (8 days), March (3 days) and April (2 days) of 2018, totaling 18 days of sampling. The total fresh weight was measured to 0.1 g of accuracy and the disc width to 0.1 cm accuracy. The parameters a and b of the equation W=a.DWb were estimated. This study provides new maximum length data for the cururu stingray.

Abstract This paper describes the fishing profile and the temporal variation in the commercial landings of elasmobranchs in a global hotspot for their conservation and investigates the variables that influenced the landings. Census data on commercial catches were obtained between April 2008 and October 2010 from nine landing sites in Bragança (Pará, northern Brazil). Five vessel types, four fishing gears, and eight fishing techniques engaged with elasmobranch capture were identified. A total of 2,357 landings were recorded, with a total production of 354 t. The highest yields were recorded in 2009, with sharks being harvested mostly by small and medium-sized vessels, and batoids, by small vessels and canoes. Drifting nets and longlines played a prominent role in elasmobranch fisheries. The results show that the landings were influenced by days at sea, which is common in tropical fisheries. The elasmobranch data series is discontinuous as statistics are absent for most fishing sites albeit imperative for proper management, as well as relevant for decision-makers focusing on their conservation. 200 201 Pará, Pará (Pará Brazil. Brazil . Brazil) types gears identified 2357 2 357 2,35 35 t 2009 mediumsized medium sized batoids canoes fisheries sea management decisionmakers decision makers 20 235 2,3 3 23 2,

ABSTRACT Bycatch species are as important as target species in the challenge of comprehensive fishery management. This is especially the case for vulnerable species such as elasmobranchs in offshore areas of the Colombian Pacific Ocean (CPO), for which information is scarce and long-term databases are used. Therefore, this study aimed to characterize the bycatch in tuna purse-seine fishery with an elasmobranch species approach using fishery data from 2000 to 2019. A total of 59 bycatch species were identified, including 27 bony fishes, 22 elasmobranchs, two mollusks, four sea turtles, and four dolphins. The total bycatch percentage was 20.8%, with elasmobranchs accounting for less than 5%. Fish aggregating devices (FADs) and class 6 vessels recorded the highest percentage of bycatch. Bony fish bycatch was mainly obtained from the border of Ecuador until 4° N across the CPO. Elasmobranchs were captured throughout the CPO, showing differences by vessel class and fishing method. The silky shark Carcharhinus falciformis was the most caught species. Elasmobranch spatial abundance and capture hotspots showed the highest values towards the northern coast, in offshore areas of Gorgona Island, southwards in offshore areas, and around Malpelo Island. FADs captured the highest number of bycatch species compared with other fishing methods, such as Tuna Associated with Dolphins (DEL), Natural Floating Objects (NAT), and Tuna not Associated (NoAs). Management recommendations for bycatch species in this fishery are provided in the CPO. management CPO , (CPO) longterm long term used Therefore purseseine purse seine 200 2019 5 identified 2 fishes mollusks turtles dolphins 208 20 8 20.8% 5% (FADs 4 method coast Island methods DEL, DEL (DEL) NAT, NAT (NAT) NoAs. NoAs . (NoAs) (CPO 201 20.8 (DEL (NAT (NoAs 20.

Resumen Este artículo analiza los factores biológicos de los elasmobranquios más comunes en Bahía Santa Elena, en el Área de Conservación Guanacaste en el Pacifico norte de Costa Rica. Debido a un vacío de información científica marino-costera que origina un fallo del sistema de manejo, no hay enfoque de resiliencia en las poblaciones sujeto de conservación. Se utilizó el método de muestreo mensual desde septiembre de 2015 hasta agosto de 2016. Mediante censo subacuático, uso de un trasmallo y visita en los puestos de recibo de pescado de Cuajiniquil se determinó la diversidad, abundancia relativa, distribución de las especies, aspectos biométricos, biología reproductiva y estructura de tallas de captura; también se aplicó una encuesta a 120 pescadores para conocer la percepción social en factores del desarrollo sostenible. Se trabajó con una muestra de 289 individuos que dio como resultado que los meses de mayor precipitación se relacionan con picos de los índices de diversidad, con poca distribución espacial, donde se presenta un remplazo estacional de especies, entre las que destaca el arribo de Rhinopterasteindachneri, Mobulamunkiana, durante los meses lluviosos y Mustelushenlei junto con Sphyrnalewini durante los vientos alisios. El periodo de desove principal para Myliobatiformes se ubica antes de diciembre, pero Urotrygonnana presenta un segundo periodo en julio. Se concluye que la biometría indica un mayor número de organismos juveniles para tiburones y adultos para rayas. La pesca con trasmallo de fondo se caracterizó por bajo rendimiento económico, lo que incide en la captura de juveniles de S. lewini, y este ingreso económico no se beneficia de los bienes naturales intangibles presentes en BSE que son patrimonio del Estado.

Abstract This article analyzes the biological factors of the most common elasmobranchs in Bahía Santa Elena, in the Guanacaste Conservation Area in the north Pacific of Costa Rica. Due to a lack of marine-coastal scientific information there is a system failure of management, leaving without a resilience approach to the populations subject to conservation. The monthly sampling method was used from September 2015 to August 2016, diversity, relative abundance, species distribution, biometric aspects, reproductive biology and catch size structure were determined by means of an underwater census, the use of a trammel net and a visit to the Cuajiniquil fish reception posts. A survey was applied to 120 fishermen to know the social perception regarding the factors of sustainable development. I worked with a sample of 289 individuals, among the main results, it was obtained that the months with the highest rainfall are related to peaks of the diversity indices, with little spatial distribution. A seasonal replacement of species is presented, highlightingthe arrival of Rhinopterasteindachneri, Mobulamunkiana, during the rainy months and Mustelushenlei and Sphyrnalewini during the Trade Winds. The main spawning period for Myliobatiformes is located before December, however Urotrygonnana presents a second period in July. It is concluded that biometry indicates a greater number of juvenile organisms for sharks and adults for rays, bottom gillnet fishing was characterized by low economic performance, which affects the capture of juveniles of S. lewini, this economic income does not benefit from the intangible natural assets present in BSE that are State assets.

Abstract Late Paleocene elasmobranch findings are reported, along with reinterpretations of some previous taxonomic identifications in two main outcrops around Talcahuano area (Biobío region, Chile), and also delimiting the exposed lithostratigraphic units. Reviewed fossils are among 15 genera, comprising the species Paraorthacodus clarkii, Squalus minor, Squalus orpiensis, Centrophorus sp., Squatina prima, Anomotodon novus, Striatolamia striata, Carcharias spp., Sylvestrilamia teretidens, Odontaspis winkleri, Palaeohypotodus speyeri, Palaeohypotodus rutoti, Isurolamna inflata, Premontreia gilberti, Physogaleus secundus, Palaeogaleus vincenti and Hypolophodon sylvestris. The main elasmobranch assemblage, collected from the San Martín outcrop, indicates deposition in a shallow lower shoreface-uppermost offshore marine environment and warm-temperate water. Moreover, this elasmobranch assemblage constrains the age of Pilpilco Formation into the middle-late Thanetian, which implies a latest Thanetian-early Ypresian age for the overlying Curanilahue Formation and a Danian-early Thanetian hiatus with the underlying Quiriquina Formation.

Resumen Paleontología e implicancias estratigráficas de un conjunto de elasmobranquios del Paleoceno Superior en Talcahuano, Chile surcentral. Se reporta el hallazgo de elasmobranquios del Paleoceno Superior, junto con la reinterpretación de algunos taxones descritos previamente en dos afloramientos principales en el área de Talcahuano (región del Biobío, Chile), que también delimitan las unidades litoestratigráficas expuestas. Los fósiles descritos se encuentran entre 15 géneros y abarcan las especies Paraorthacodus clarkii, Squalus minor, Squalus orpiensis, Centrophorus sp., Squatina prima, Anomotodon novus, Striatolamia striata, Carcharias spp., Sylvestrilamia teretidens, Odontaspis winkleri, Palaeohypotodus speyeri, Palaeohypotodus rutoti, Isurolamna inflata, Premontreia gilberti, Physogaleus secundus, Palaeogaleus vincenti e Hypolophodon sylvestris. El conjunto principal de elasmobranquios, obtenidos desde el afloramiento de Cerro San Martín, indica una depositación en un ambiente marino somero de shoreface inferior al offshore más superior, con una temperatura del agua templada cálida. Más aún, este conjunto de elasmobranquios acota la edad de la Formación Pilpilco al Thanetiano medio a tardío, subsecuentemente implicando una edad para la sobreyaciente Formación Curanilahue entre finales del Thanetiano al Ypresiano temprano y un hiato Daniano-Thanetiano temprano con respecto a la subyaciente Formación Quiriquina.

RESUMEN: En los peces elasmobranquios, las variaciones en la organización estructural general del cerebelo se han explorado ampliamente. Las características histológicas básicas del cerebelo, aunque se conservan en el grupo, pero la descripción comparativa de las variaciones celulares sutiles es limitada. El presente estudio tiene como objetivo explorar las variaciones histológicas y celulares en diferentes capas de la corteza cerebelosa de las especies representativas de elasmobranquios pertenecientes a diferentes hábitats. Nuestros hallazgos mostraron que la arquitectura histológica de la capa granular del cerebelo entre las especies examinadas varía notablemente. Se observó un gran aumento de la densidad celular en todas las capas del cerebelo en las especies representativas de tiburón en comparación con la raya. Luego, los hallazgos se compararon y discutieron con referencia a su hábitat y comportamiento.

SUMMARY: In elasmobranch fishes, variations in gross structural organization of cerebellum has been extensively explored. The basic histological features of cerebellum although conserved in the group but the comparative account on subtle cellular variations is largely underestimated. The present study aims to explore the histological and cellular variations in different layers of cerebellar cortex of the representative elasmobranchs’ species belonging to different habitat. Our findings showed that the histological architecture of cerebellar granular layer between the examined species varies noticeably. By and large increase cellular density were observed in all the layers of cerebellum in the representative species of shark compared to ray. The findings were then compared and discussed with reference to their habitat and behavior.

Abstract Reviews can be useful to provide an overview of specific knowledge areas to facilitate research guidelines and the comparison of study results. Therefore, we aimed to detect regions, environments, and taxonomic groups of elasmobranch that lack information on their feeding ecology and consequently need further attention. Using specific keywords on diet and feeding studies, we searched for articles on the trophic and feeding ecology of elasmobranchs. We found an increase in studies over the last 24 years, with an emphasis on stomach contents and stable isotopes. The USA, Australia, Mexico, Argentina, and Brazil were the countries with the highest number of published articles. Australia, the USA, Argentina, Brazil, Mexico, South Africa, Spain, Uruguay and India were the countries with the highest number of species studied. Estuarine and freshwater environments seem to need more attention, since studies on species in these environments were scarce (~3%). The total number of shark and ray species studied showed no significant differences (164 and 186, respectively), but most of the articles reviewed concerned sharks (67.5%). The larger elasmobranch families also need more attention, especially demersal species such as Rajidae, Dasyatidae, Arhynchobatidae, and Sycliorhinidae. Feeding studies only analyze some of the data deficient (DD) species (~7%) included in the IUCN Red List, pointing to the need to obtain more information about them. results Therefore regions attention elasmobranchs 2 years isotopes USA Australia Mexico Argentina Africa Spain ~3%. 3 ~3% . (~3%) 164 (16 186 respectively, respectively , respectively) 67.5%. 675 67.5% 67 5 (67.5%) Rajidae Dasyatidae Arhynchobatidae Sycliorhinidae DD (DD ~7% 7 (~7% List them ~3 (~3% 16 (1 18 67.5 6 (67.5% ~7 (~7 ~ (~3 1 ( 67. (67.5 (~ (67. (67 (6

Resumen Introducción: El conocimiento sobre el comportamiento reproductivo y requisitos de hábitat de apareamiento de los tiburones grandes, incluido el tiburón limón, Negaprion brevirostris, es escaso, lo que dificulta los esfuerzos de conservación. Objetivo: Describir un área en el Océano Atlántico ecuatorial utilizada como zona de apareamiento y las interacciones precopulatorias del tiburón limón con base en informes proporcionados por ciencia ciudadana. Métodos: Buzos recreativos, guías de buceo y guardaparques del Área Marina Protegida (AMP) en el archipiélago Fernando de Noronha (FEN) llevaron registros de comportamientos de cortejo, hembras con cicatrices de apareamiento, hembras preñadas y machos adultos, entre 2004 y 2019. Resultados: Las aguas poco profundas entre 0.5 y 2 m de profundidad son utilizadas como áreas de apareamiento por N. brevirostris durante el verano austral (diciembre a marzo). Un lugar específico, dentro del AMP (laguna de Buraco da Raquel), fue identificado como el principal sitio de agregación y apareamiento de adultos de N. brevirostris en FEN. Conclusiones: Registros de ciencia ciudadana permitieron identificar aguas poco profundas como sitios clave para la reproducción de este tiburón en FEN. Los resultados resaltan el potencial de las contribuciones de la ciencia ciudadana al conocimiento de los tiburones en la naturaleza y muestran que las AMP son esenciales para la conservación del hábitat de tiburones con poblaciones decrecientes a lo largo de la costa brasileña, como N. brevirostris. Presentamos recomendaciones de gestión para proteger a N. Brevirostri, allí y en otros lugares.

Abstract Introduction: Knowledge on the mating behavior and habitat requirements of large sharks, including the lemon shark, Negaprion brevirostris, is scarce, hampering conservation efforts. Objective: To describe an area in the Equatorial Atlantic used as a mating ground by N. brevirostris, as well as part of the species pre-copulatory behaviors based on citizen reports. Methods: Between 2004 and 2019, recreational divers, dive guides and rangers from the Marine Protected Area (MPA) in Fernando de Noronha Archipelago (FEN) recorded courtship behaviour, females with mating scars, pregnant females, and adult males. Results: N. brevirostris was recorded mating in shallow waters (0.5-2 m deep) during the austral summer (December to March). A specific location in the MPA, Buraco da Raquel lagoon, was the main aggregation and mating site for adult N. brevirostris in FEN. Conclusions: Citizen science records allowed the identification of shallow waters as key sites for the reproduction of this shark in FEN. Results highlight the potential of citizen science contributions to knowledge of sharks in nature and show MPAs as essential for habitat conservation of sharks with decreasing populations along the Brazilian coast, such as N. brevirostris. We present management recommendations to protect N. brevirostris there and elsewhere.

ABSTRACT There are very little data on Central America and the Western Caribbean elasmobranch populations. Here we present the first results of standardized fisheries-independent monitoring of sharks and rays in Panama’s Bocas del Toro Archipelago over four consecutive years. Using baited remote underwater videos (BRUVs), underwater visual census (UVC), and scientific longline, we provide baseline data on the composition, relative abundance, distribution, and demographics of seven shark species and six rays observed during the study. Observations differed among methods and habitats, with BRUVs (n = 148) more effective for assessing shark diversity and abundance and UVC (n = 108) more effective for assessing ray abundance. Nurse sharks (Ginglymostoma cirratum) and southern stingrays (Hypanus americanus) were the most commonly observed species overall (frequency of occurrence = 30.4 and 18.9%, respectively). Depth, temperature, and protected area status significantly affected the relative abundance of sharks and rays based on UVC and BRUV data. The use of scientific longlines (n = 55) highlighted the lagoon habitat as a potential nursery site for blacktip sharks (Carcharhinus limbatus), with juvenile (average total length = 113 cm) individuals representing 58% of longline captures. The results provide a current baseline for elasmobranch communities that can further aid in the conservation and management of these species nationally and regionally.

Resumo A informação de referência hematológica e bioquímica do sangue é importante para estabelecer o estado fisiológico das populações de arraias de água doce e melhorar os protocolos de cuidado e manejo em ambientes artificiais. Aqui, usamos uma espécie comercial de arraia de água doce com elevadas taxas de mortalidade no mercado (Potamotrygon magdalenae) como espécie exemplo para compreender de que modo os ambientes artificiais e os protocolos de manipulação influenciam o estado fisiológico das arraias de água doce em cativeiro. Para este fim, foi coletado sangue de cinco machos adultos e seis fêmeas adultas para realizar contagens completas de células sanguíneas e análises bioquímicas de sangue. Todos os animais amostrados mostraram boa condição corpórea, sem diferenças entre os sexos. Diferenças entre os sexos foram encontradas só na contagem diferencial de linfócitos. Os resultados de células sanguíneas vermelhas foram consistentes com potamotrigonídeos previamente estudados, enquanto o leucograma revelou valores mais elevados de leucócitos, trombócitos, heterófilos e linfócitos em P. magdalenae, em comparação com outros potamotrigonídeos. Todos os tipos de leucócitos descritos para elasmobrânquios foram encontrados, exceto para neutrófilos e basófilos. Todos os tipos de leucócitos descritos para elasmobrânquios foram encontrados, exceto para neutrófilos e basófilos. Os metabólitos do sangue mostraram influência da dieta ex situ nas proteínas totais, triglicerídeos e colesterol. Os resultados da glicose foram consistentes, enquanto a ureia mostrou níveis mais baixos do que os registrados para outras espécies de arraias de água doce. Os resultados da glicose foram consistentes, enquanto a ureia mostrou níveis mais baixos em P. magdalenae. Estes resultados enfatizam a importância da análise física, fisiológica e de saúde em arraias de água doce como parte da avaliação do bem-estar para melhorar os protocolos de monitoramento e as taxas de sobrevivência em aquários públicos ou privados.

Abstract Hematological and blood biochemical reference information is important to establish physiological status of freshwater stingray populations and improve care and management protocols in artificial environments. Here, we used a commercial freshwater stingray with high mortality rates in the market (Potamotrygon magdalenae), as an example to understand how artificial environments and handling protocols influence physiological status of captive freshwater stingrays. To this purpose, blood from five adult males and six adult females was collected to perform complete blood counts and blood chemistry analyses. All sampled animals showed good body condition with no differences between sexes. Differences between sexes were only found for the differential count of lymphocytes. Red blood results were consistent with previously studied potamotrygonids while white blood results showed higher values of leukocytes, thrombocytes, heterophils and lymphocytes in P. magdalenae compared to other Potamotrygonids. All types of leukocytes described for elasmobranchs were found except neutrophils and basophils. Blood metabolites showed an influence of ex situ diet in total protein, triglycerides and cholesterol. Glucose results were consistent while urea showed lower levels than those recorded for other freshwater stingrays. These results highlight the importance of physical, physiological and health analysis in freshwater stingrays as a part of welfare assessment to improve monitoring protocols and survival rates in public or private aquaria.

Resumen Introducción: La identificación de hábitats críticos para especies vulnerables de elasmobranquios es crucial para tomar medidas de conservación efectivas. La manta diablo o raya de Munk (Mobula munkiana) es endémica del Pacífico Oriental y se sabe poco sobre su biología, ecología y uso de hábitat. Como filtradores, se asume que se concentran en regiones de afloramiento con alta productividad; sus poblaciones se consideran en disminución y requieren información urgente para fundamentar medidas de conservación. Objetivo: El estudio se realizó para obtener información sobre un comportamiento de alimentación observado en juveniles de M. munkiana, con el fin de proporcionar más información sobre las primeras etapas de vida de esta especie considerada vulnerable a la extinción. Métodos: De junio a setiembre de 2017 y en agosto de 2018, se observó el comportamiento de alimentación de los juveniles de M. munkiana en dos bahías poco profundas de Punta Descartes, en el Pacífico norte de Costa Rica. Los individuos fueron capturados utilizando un método no letal para obtener datos sobre el tamaño, peso y sexo. Se tomaron 100 muestras de plancton en las bahías para inferir la composición de la dieta. Resultados: Las rayas mostraron un comportamiento de natación repetitivo paralelo a la playa, alimentándose exclusivamente en la zona de rompimiento de las olas en marea baja, a menos de 50 cm de profundidad. Un total de 12 rayas M. munkiana (11 vivas y una encontrada muerta) indicaron una agregación de juveniles para alimentarse. Los anchos de disco variaron de 490 a 610 mm y el peso entre 1400 a 2300 g. La proporción sexual (machos: hembras) fue de 3:1. En la zona donde rompían las olas se encontró principalmente el orden Mysidaceae. Conclusiones: El comportamiento específico y la ocurrencia estacional de M. munkiana en la zona de estudio parecen estar impulsados por la abundancia de presas. Se necesita más investigación para concluir la presencia de adultos reproductivos a mayor profundidad y sobre el uso de hábitat en los alrededores de Punta Descartes durante todo el año. Esta área se encuentra amenazada por un desarrollo insostenible y requiere estrategias de manejo realistas para garantizar la supervivencia de especies vulnerables y sus hábitats críticos.

Abstract Introduction: Identifying critical habitats for vulnerable elasmobranch species is crucial for effective conservation measures. The Munk’s devil ray (Mobula munkiana) is endemic to the Eastern Pacific, but yet little is known about its biology, ecology, and habitat use. As filter feeders, it is assumed that this species concentrates at high-productive upwelling regions, such as the Costa Rican Dome. Like many elasmobranchs, its populations are highly depleted and require urgent information to inform better conservation measures. Objective: The study was conducted to gain information on a unique behavior observed in juvenile M. munkiana, so further information can be provided on early life stages of this vulnerable species. Methods: From June to September 2017 and in August 2018, the feeding behavior of juvenile Mobula munkiana was observed in two shallow bays located at Punta Descartes, North Pacific Costa Rica. Individuals were captured using a non-lethal method to obtain data on size, weight, and sex distribution. Plankton samples (n = 100) were taken at both bays throughout the months to infer diet composition. Results: Munk’s devil rays showed a repetitive swimming movement parallel to the beach, feeding exclusively in the shallow breaking zone of the low tide waves at depth <50cm. A total of 12 M. munkiana (11 live and one found dead) indicated a juvenile feeding aggregation ranging from 490 - 610mm in disk width and 1400 - 2300gr in weight. The sex ratio (males to females) was 3:1. Zooplankton of the order Mysidacae was found in the highest abundance in the breaking zone. Conclusions: The specific behavior and seasonal occurrence of juvenile Munk’s devil rays in this area seem to be driven by prey abundance. More research is needed to conclude the presence of reproductive adults at deeper depths and the year-round habitat use of Punta Descartes. The area is threatened by unsustainable development and requires realistic management strategies to guarantee the survival of vulnerable species and their critical habitats.

SUMMARY: The dermal denticles are dermal structures present in the group of chondrichthyans, they have a very important role in their biology and they have been used as a taxonomic character that allows to recognize groups or species. Therefore, in the present work, the dermal morphology of the juveniles of two species of shovel sharks, Sphyrna tiburo and S. vespertina, whose evolutionary origin is related to the closure of the Central American isthmus, is compared. For this, dermal samples (1 cm2) from three body regions were obtained and processed to obtain high resolution images by means of scanning electron microscopy (SEM). The denticles of both species have a common morphological pattern, with variations in the length of the ridge extensions, free area and overlapping of the denticles, and the degree of notoriety of the microstructural ornamentation.

RESUMEN: Los dentículos dérmicos son estructuras dermales presentes en el grupo de los condrictios, tienen un papel muy importante en su biología y se les ha utilizado como un carácter taxonómico que permiten reconocer grupos o especies. Por lo que en el presente trabajo se compara la morfología dermal de los juveniles de dos especies de tiburones pala, Sphyrna tiburo y S. vespertina, cuyo origen evolutivo está emparentado con el cierre del istmo centroaméricano. Para ello se obtuvieron muestras dermales (1 cm2) de tres regiones corporales y se procesaron para obtener imágenes de alta resolución por medio de Microscopia electrónica de barrido (MEB). Los dentículos de ambas especies tienen un patrón morfológico común, con variaciones en la longitud de las prolongaciones de las crestas, área libre y superposición de los dentículos, y grado de notoriedad de la ornamentación microestructural.

Resumo: Elasmobrânquios apresentam os maiores declínios populacionais entre os vertebrados, sendo considerado um dos grupos com maior risco de extinção. O Litoral Amazônico Brasileiro (BAC) é considerado uma área prioritária para conservação de elasmobrânquios, pois várias espécies são endêmicas da região, e a maioria delas estão ameaçadas de extinção. O presente estudo fez uma análise cientométrica aplicando o método IRAMUTEQ (Interface de R pour les Analyses Multidimensionnelles de Textes et de Questionnaires) para avaliar as tendências de pesquisas com elasmobrânquios no BAC nas últimas quatro décadas. Dez tendências de pesquisa foram identificadas, destacando-se “Biodiversidade”, “Reprodução”, “Ecologia trófica” e “Conservação”. Entretanto, a maioria das publicações encontradas é voltada para o conhecimento da diversidade e abundância das espécies na região, sendo o número de estudos voltados para a reprodução, alimentação e outros aspectos da biologia e ecologia de elasmobrânquios do BAC menos expressivo. Apesar da área de investigação “Conservação” ter se destacado na busca, a quantidade de informações relevantes para que medidas de manejo e conservação possam ser implementadas ainda é baixa. Por fim, apesar de seguir a tendência mundial de estudos com elasmobrânquios entre 2000 a 2010, as investigações sobre o BAC precisam avançar, especialmente considerando o baixo nível de informações básicas sobre a maioria das espécies (biologia e dinâmica populacional) e o conhecimento incompleto da composição específica das espécies de elasmobrânquios em toda a área, aspectos relevantes para a conservação e estudos mais aplicados e que contem com metodologias e tecnologias mais recentes.

Abstract: Elasmobranchs exhibit the biggest population declines among vertebrates, being considered one of the groups with the highest risk of extinction. The Brazilian Amazon Coast (BAC) is considered a priority area for elasmobranch conservation, as many species are endemic to the region, and most of them are threatened with extinction. The present study made a scientometric analysis using the IRAMUTEQ method (Interface de R pour les Analyses Multidimensionnelles de Textes et de Questionnaires) to evaluate the trends of research with elasmobranchs in BAC in the last four decades. Ten research trends were identified, highlighting “Biodiversity”, “Reproduction”, “Trophic Ecology” and “Conservation”. However, most of the publications found are aimed at understanding the diversity and abundance of species in the region, with the number of studies focused on reproduction, feeding and other aspects of the biology and ecology of elasmobranchs in the BAC being less expressive. Although the research area “Conservation” stood out in the search, the amount of relevant information so that management and conservation measures can be implemented is still low. Lastly, despite following the global trend of studies with elasmobranchs between 2000 and 2010, investigations into the BAC need to advance, especially considering the poor level of basic information on most species (Biology and population dynamics) and the incomplete knowledge of specific composition of elasmobranch species in the entire area, aspects relevant to conservation and more applied studies that rely on more recent methodologies and technologies.

Resumo: Inventários de ictiofauna com métodos tradicionais de captura são indesejáveis em reservas marinhas. O censo visual subaquático, porém, sofre o viés das interações peixe-mergulhador, tais como comportamentos de timidez ou fuga exercido pelas grandes espécies-alvo de pressões pesqueiras, incluindo, a caça submarina. Esse estudo representa o primeiro inventário da ictiofauna marinha do Arquipélago de Fernando de Noronha, costa nordeste do Brasil, utilizando sistemas não-destrutivos independentes de vídeos subaquáticos com iscas (BRUVS). Uma elevada riqueza de espécies de peixes, com 66 espécies de 28 famílias e 10 ordens, incluindo cinco espécies de elasmobrânquios e outros grandes peixes predadores como barracudas, garoupas e dentões, foi registrada em 81 amostras de vídeos subaquáticos. Adicionalmente, todos os 4.398 indivíduos avistados foram associados a até quatro diferentes tipos de habitats bentônicos. Um catálogo de imagens subaquáticas dos peixes e uma lista de espécies detalhada com informações adicionais, tais como o status de conservação, são fornecidos.

Abstract: Fish fauna assessments with traditional catch methods are undesired in marine reserves. Underwater visual census on the other hand is biased due to fish-diver interactions, such as shyness or avoidance behavior of large-bodied target species. This study presents the first marine ichthyofauna inventory of the Fernando de Noronha Archipelago, off northeastern Brazil, sampled with non-destructive, independent Baited Remote Underwater Video Systems (BRUVS). High fish species richness, totaling 66 species from 28 families and 10 orders, including five elasmobranch species and other large predatory fish, such as barracudas, groupers and snappers, were recorded from 81 underwater video samples. Additionally, all of the 4,398 individuals sighted were associated to up to four different benthic habitat types. A catalog of underwater fish images and a detailed species list with additional information, such as conservation status, are provided.