Trindade and Martin Vaz (TMV) is a highly isolated, oceanic volcanic archipelago located approximately 1200 km off the Brazilian coast and about 4200 km away from the nearest African coast. It has been almost 70 years since the first sea star, “Astropecten sp.”, was recorded from Trindade in 1951. In the following years (1955–1971; 2006) six sea star species were added to the archipelago’s fauna. After that period, however, research on shallow water echinoderms has not been conducted in TMV and no further sea star species have been recorded from there since. From 2012 to 2019, 263 daytime SCUBA diving and intertidal samplings conducted at TMV yielded 91 lots of sea stars in 7 species: Linckia guildingi Gray, 1840; Oreaster reticulatus (Linnaeus, 1758); Astropecten aff. antillensis Lütken, 1859; Copidaster lymani A. H. Clark, 1948; Luidia alternata alternata (Say, 1825); Mithrodia clavigera (Lamarck, 1816); and Ophidiaster guildingi Gray, 1840. The last five species in this list represent new records to the archipelago, with C. lymani also being the first record of the species in the southwestern Atlantic. Five shallow water species previously known from TMV have not been observed in the present survey: Asterinides folium (Lütken, 1860), Astropecten brasiliensis Müller & Troschel, 1842, Astropecten cingulatus Sladen, 1883, Linckia nodosa Perrier, 1875, and Ophidiaster alexandri Verrill, 1915. Twelve sea star species are currently known from shallow waters of TMV. A list of all sea star species known from shallow waters (intertidal down to 100 meters) of the tropical southern-central Atlantic oceanic archipelagoes and islands (Ascension, Cape Verde, Fernando de Noronha, Gulf of Guinea, Rocas Atoll, Saint Helena, Trindade and Martin Vaz) with their gross distribution in the Atlantic Ocean was compiled in order to explore the existence of patterns of geographic distribution for the shallow water sea star species in the tropical southern-central Atlantic oceanic islands. It has been found that 44% of the species from TMV are of western Atlantic affinity, 33% amphi-Atlantic, and 22% circumtropical in distribution. No endemic sea star species are known from TMV to date. The even more remote Ascension (ASC) and Saint Helena (STH) are more of a mosaic than TMV. The ASC and STH fauna consist of 8 and 11 sea star species, respectively. Their endemic component totals to 25% and 27%, respectively. STH has more amphi-Atlantic and eastern Atlantic sea star species (27% each) than ASC (25% and 12.5%, respectively). Twenty-five percent of the sea star species in ASC are circumtropical in distribution, whereas no circumtropical species have been found in STH. The western Atlantic (WA) component comparatively to the eastern Atlantic (EA) one is of minor significance in STH (18% versus 27%, respectively), whereas the WA and EA components contribute equally to the taxonomic composition in ASC (12.5% each). However, patterns of faunal affinities in both islands are actually taxon-dependent.
Describing ontogenetic morphological change is an important part of integrative taxonomy; still, most taxonomic studies are based only on adult characters. Here, we provide illustrations and a morphological description of the sea stars from Bahia, including ontogenetic and intraspecific variation, and identify taxonomic issues. A total of 293 specimens from different localities along the Bahia State coastline and comparative material from other localities were examined. Eighteen species (11 genera, eight families) of Asteroidea were identified; Astropectinidae was the most representative family. All species identified also occur in subtropical Brazilian waters and most species are from shallow water habitats with soft bottoms. Most observed ontogenetic variation was quantitative in nature, such as the increase in the number of spines in the furrow and of spinelets in the paxillae with specimen growth. Genera that require further taxonomic studies are Astropecten and Othilia, whose specimens are commonly misidentified in local studies. One third of the species from Bahia are currently classified as “Vulnerable” in the Brazilian Red List, but baseline data on the population biology of these species are scarce. An illustrated identification key to the 65 Brazilian sea star species is also provided. This taxonomic study will facilitate the identification of specimens occurring along the Brazilian coast and help scientists and policy makers to establish the conservation status of the Brazilian species.
Revisão do gênero Narcissia Gray, 1840 (Echinodermata: Asteroidea: Ophidiasteridae): da morfologia à taxonomia Revision of the genus Narcissia Gray, 1840 (Echinodermata: Asteroidea: Ophidiasteridae): from morphology to taxonomy São Paulo 2019 RESUMO Desde a revisão taxonômica dos Ophidiasteridae por H. L. Clark (1921), em que 20 gêneros foram reconhecidos como válidos, vários novos gêneros e espécies foram incluídos nesta família, e os limites entre alguns deles se tornaram largamente arbitrários. Isso também se aplica a Narcissia Gray, 1840, cuja morfologia e taxonomia são, ainda hoje, muito mal compreendidas. Os principais objetivos desta pesquisa foram: revisar a taxonomia do gênero Narcissia ao longo de toda a sua área de distribuição, a partir de estudos morfológicos; redescrever e caracterizar, morfologicamente, Narcissia trigonaria Sladen, 1889 strictu senso; caracterizar, morfologicamente, N. canariensis (d'Orbigny, 1839) e N. ahearnae Pawson, 2007, as duas espécies válidas mais semelhantes a N. trigonaria; rever a validade de N. trigonaria helenae Mortensen, 1933; rever a validade de N. gracilis malpeloensis Downey, 1975. Cerca de 370 espécimes do gênero Narcissia foram analisados: dois indivíduos de N. ahearnae, 82 espécimes de N. canariensis, 44 de N. gracilis e 242 de N. trigonaria. O material que serviu de base para nossos estudos pertence às coleções de museus nacionais e estrangeiras. A terminologia para estruturas morfológicas seguiu Clark (1921), Turner & Dearborn (1972), Clark e Downey (1992) e Gale (2011). As pedicelárias foram classificadas de acordo com Jangoux e Lambert (1988). Todas as estruturas morfológicas de importância taxonômica foram ilustradas. E, pela primeira vez, os caracteres internos deste grupo foram estudados, a partir de microscopia eletrônica e tomografia. Uma nova diagnose para o gênero Narcissia foi disponibilizada. Todas as espécies do gênero foram revisadas e morfologicamente redescritas.Narcissia trigonaria, descrita a partir de um juvenil, foi redescrita a partir de um exemplar adulto, proveniente da localidade tipo (Bahia). Narcissia ahearnae é considerada uma espécie válida, e N. canariensis e N. trigonaria entidades distintas. Narcissia trigonaria helenae foi colocada na sinonímia de N. trigonaria, e N. gracilis malpeloensis entrou para a sinonímia de N. gracilis. A classificação de Narcissia, dentro da Família Ophidiasteridae, foi contestada, a partir de caracteres morfológicos. Os dados obtidos neste trabalho são, de longe, os mais completos já adquiridos para o gênero Narcissia e, futuramente, podem servir de base para os estudos morfológicos de outros grupos da Classe Asteroidea. ABSTRACTSince the taxonomic revision of the Ophidiasteridae by H. L. Clark (1921), in which 20 genera were recognized as valid, several new genera and species were included in this family, and the boundaries between some of them became largely arbitrary. This also applies to Narcissia Gray, 1840, whose morphology and taxonomy are still very poorly understood today. The main goals of th...
Since the taxonomic revision of the Ophidiasteridae by H.L. Clark (1921), in which 20 genera were recognized as valid, several new genera and species were included in this family, and the boundaries between some of them became largely arbitrary. This also applies to Narcissia Gray, 1840, whose morphology and taxonomy are still very poorly understood today. The main goals of this research were: review the taxonomy of the genus Narcissia, from morphological studies; redescribe N. trigonaria Sladen, 1889s. str.; characterize N. canariensis (d'Orbigny, 1839) and N. gracilis A.H. Clark, 1916, the two valid species most similar to N. trigonaria; review the validity of N. ahearnae Pawson, 2007 and N. trigonaria var. helenae Mortensen, 1933; review the validity of N. gracilis malpeloensis Downey, 1975. Altogether 370 specimens were analysed. All morphological structures of taxonomic importance have been illustrated, and, for the first time, the internal characters of this group were studied, from electron microscopy and microtomography. A new diagnosis for the genus Narcissia was constructed. Narcissia trigonaria was redescribed from a large specimen, from the type locality (Bahia, Brazil). Narcissia ahearnae is considered a valid species, and N. canariensis and N. trigonaria distinct entities. Narcissia trigonaria var. helenae is placed in the synonymy of N. trigonaria, and N. gracilis malpeloensis into the synonymy of N. gracilis. The dataset obtained in this work is by far the most complete acquired for the genus Narcissia.
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