arrow_rtl    arrowsig

Rev. biol. mar. oceanogr. 51(1): 193-195

Nota Científica


Thalamita bevisi en Isla de Pascua, Chile (Decapoda, Brachyura, Portunoida)

This email address is being protected from spambots. You need JavaScript enabled to view it.1,2 y Guillermo Guzmán1,2

1Facultad de Recursos Naturales Renovables, Universidad Arturo Prat, Avenida Arturo Prat Nº 2120, Código Postal 1110939, Casilla de Correos 121, Iquique, Chile
2Laboratorio de Carcinología, Museo de Zoología, Universidad de São Paulo. Avenida Nazaré 481, CEP 0426300 - SP, São Paulo, Brasil

emailButton  This email address is being protected from spambots. You need JavaScript enabled to view it.

The southwestern Gulf of California has high-value commercial fisheries; however, there are few studies of the taxonomic diversity of fish in this area. Surveys of taxonomic diversity of the fish assemblage at 8 localities near the shore of Bahía de La Paz were undertaken from March 2002 to April 2003. Seasonal changes in diversity of rocky reef fish were analyzed, including taxonomic distance among fish species, using the alpha, alpha average, beta, and gamma diversity indices, the taxonomic distinctness index (TD D*), and the average taxonomic distinctness index (AvTD D+). Submarine visual censuses were carried out along 48 transects measuring 100 × 5 m (500 m2) at 5 m average depth from 09:00-16:00 h. Two seasons were studied: winter with an average temperature of 22.57°C, and summer with an average temperature of 27.09°C. 24,633 fishes, belonging to 92 species and 67 genera were recorded. According to the alpha average, beta, and gamma diversity indices, August had the highest diversity (19.5, 40.5, and 60 species, respectively), and December had the lowest diversity (20.6, 27.4, and 48 species, respectively). Spatial analysis of TD and AvTD were not significantly different, and analysis by season of these indices was not significant different. Greater anthropogenic impact would cause differences in TD and AvTD found at El Guano compared with other locations.
Four species belonging to genus Thalamita have been reported from the Easter Island, South Pacific, from Chile. The controversial presence of T. bevisi in Easter Island is confirmed, with a new record of recent specimens. The present study provides taxonomic information, including the examination of the morphology of the first gonopod.

Key words: Brachyura, Portunidae, Thalamita bevisi, Rapa Nui, Easter Island