996 resultados para Travassosisca n. g. n. spp.


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Fish assemblages from two sandy beaches in the lower Purus river (Amazonas, Brazil) were compared. Four sampling groups were represented by: day and night samples in sandy beach inside the Reserva Biológica de Abufari (biological reserve) and day and night samples in the Reserva de Desenvolvimento Sustentável Piagaçu-Purus (sustainable development reserve). Samples were collected during low water levels (November) in 2007. The fish were sampled by means of seines with mesh size of 5 mm between opposing knots, 11 m long and 6 m wide. A total of 112 fish species belonging to nine orders and 27 families was captured. The vast majority of the dominant forms consisted of small fishes (< 100 mm SL) or juveniles. Samples collected in Abufari at night presented more specimens (3,540), higher richness (84 spp.), larger total biomass (76,614 g) and higher diversity (H'= 2.57) than the other groups. The composition of fish assemblages was significantly different among all analyzed groups (ANOSIM, p < 0.0001, R= 0.71). NMDS analysis also clustered all species in four distinct groups according to species composition per period and site. SIMPER analyses showed that 80% of variation of species composition among the groups examined was due to 12 species. However, fish composition did not show any correlation with the abiotic factors examined. Different levels of use in both reserves may explain differences in fish composition.

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Os corais exóticos coral-sol (Tubastraea coccinea Lesson, 1829 e T. tagusensis Wells, 1982) invadiram as comunidades biológicas sésseis dos costões rochosos da Baía da Ilha Grande, Rio de Janeiro, Brasil. Estruturas artificiais (piers, decks ou cais) foram selecionadas em quatro locais na Ilha Grande, e comparadas com substratos naturais adjacentes através de quantificação da densidade de cada espécie de Tubastraea, além da porcentagem de cobertura da biota bêntica. A densidade média geral de Tubastraea tagusensis foi de 80,3 indivíduos.m-2, aproximadamente o dobro encontrado para T. coccinea. Tendo em vista que sua presena alterou as abundâncias relativas e a riqueza de espécies, ambas as espécies invasoras modificaram a estrutura das comunidades invadidas. Tubastraea coccinea foi mais abundante em substratos artificiais do que naturais, porém, no foi detectada diferena na abundância de Tubastraea tagusensis entre substratos. A abundância de ambas as espécies variou com a profundidade e o local, e houve uma relação positiva entre a idade do substrato artificial e a abundância dos corais. Aparentemente T. tagusensis é competitivamente superior à T. coccinea, com uma inserção maior nas comunidades nativas em substratos naturais. Ambas as espécies tem grande potencial competitivo e podem utilizar substratos artificiais para iniciar seu estabelecimento em novos locais.

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Gargaphia inca Monte, 1943 was synonymized with G. opima Drake, 1931 without any declared reasons. Gargaphia inca is known only from its type location (Satipo, Peru), and G. opima from Colombia (Villavencio) and Peru (Cam. Del Pichis, type-locality), in addition to the new records here presented, including the first record for Ecuador. Both species are redescribed, and the status of G. inca is revisited and raised from synonymy. Illustrations of some of the most remarkable differences between these taxa are provided, as well as dorsal habitus images. Discussions on the genus systematic status and this nomenclatural act are presented.

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