Community structure of conspicuous echinoderms of three islands from the Gulf of California, Mexico

摘要

The objective of this study was to analyze the community structure of conspicuous echinoderms in three islands in the southern Gulf of California, San Jose, Espiritu Santo and Cerralvo. A total of 140 belt transects (25 x 2 m) were used to assess the echinoderm communities. We estimated species richness, abundance, diversity and evenness. 23 echinoderms species were identified (12 Asteroids, 7 Echinoids and 4 Holothurians). San Jose showed the highest values of richness and the most diverse was Cerralvo. Asteroids were well distributed along the islands, but Espiritu Santo had more species. Phataria unifascialis was the most abundant asteroid in the three islands. In San Jose, the most abundant echinoid was Toxopneustes roseus, in Espiritu Santo was Eucidaris thouarsii and in Cerralvo was Tripneustes depress us. The most abundant holothurian was Holothuria fuscoscinerea, found in San Jose and Espiritu Santo, but in Cerralvo was Isostichopus fuscus, an important protected species.