LAUSR

espanolSe estudio la Subclase Opisthobranchia en Acapulco. Los objetivos fueron conocer la riqueza de especies, la composicion de la comunidad a partir de las abundancias, disposicion espacial local y la ubicacion jerarquica de las especies, ademas comparar la similitud entre sitios. Se muestreo de 2009 a 2012 en 5 sitios, durante el dia, en marea baja, bimensualmente. En la zona intermareal rocosa se hicieron muestreos siguiendo la linea de costa y en el submareal se efectuaron inmersiones hasta 4 m por buceo libre. Se identificaron 59 especies, 5 mas identificadas hasta genero. Son nuevos registros de distribucion para Acapulco 28 especies. El Orden Nudibranchia fue el de mayor cantidad de familias, riqueza de especies y abundancia. La mayor riqueza de especies se encontro en la familia Dorididae y la mayor abundancia en la familia Facelinidae. Las especies mas abundantes fueron Phidiana lascrucensis, Elysia diomedea, Pleurobranchus aerolatus, Glossodoris sedna y Polycera alabe. El 24,44% de las especies presento disposicion espacial local ampliada, el 32,8% disposicion semirestringida y el 43,75% restringida. Se encontro que 19 especies fueron dominantes y representaron el 28,78%. Se hallo la mayor similitud en abundancia en los sitios Tlacopanocha y Parque de la Reina, que presentan caracteristicas de intensidad de oleaje bajo y sustratos muy heterogeneos. La riqueza de especies encontrada es de las mas altas reportada para el Pacifico Americano. Se amplia considerablemente el listado de especies conocidas para Acapulco y se contribuye al conocimiento de la composicion de la comunidad de la Subclase Opisthobranchia. EnglishSubclass Opisthobranchia in Acapulco was studied. The objectives were to know the species richness, community composition based on the abundances, local spatial arrangement and hierarchical location of the species, also compare the similarity between sites. Sampling was carried out from 2009 to 2012 at 5 sites during the day, at low tide, every two months. On the rocky intertidal zone samplings were carried out along the shoreline and in the subtidal zone, sampling was carried out using snorkel conducting divings to a maximum depth of 4 m. Fifty-nine species were identified, and 5 were identified to genus level. Twenty-eight new records were determined to Acapulco. Nudibranchia has the highest value in the number of families, species richness and abundance. The highest species richness was found in the Dorididae family and the greater abundance in the Facelinidae family. The most abundant species were Phidiana lascrucensis, Elysia diomedea, Pleurobranchus aerolatus, Glossodoris sedna and Polycera alabe. Twenty four percent of the species has wide local distribution, meanwhile 32.8% was semi restricted and 43.75% restricted. Were found 19 dominant species, representing 28.78% of the total species. The greatest similarity in abundance was estimated for Tlacopanocha and Parque de la Reina sites. These sites are characterized by similar features in the low wave intensity and a heterogeneous substrate. The species richness found is the highest reported for the American Pacific. Acapulco list of known species of Subclass Opistobranchia is considerably expands and it contributes to the knowledge of the composition of the community of this Subclass.