Equinodermos del Parque Nacional Marino Ballena, Pacífico, Costa Rica / Echinoderms from Marino Ballena National Park, Pacific, Costa Rica

A total of 25 species of echinoderms (four asteroids, six ophiuroids, five echinoids and ten holothurians) were recorded at Marino Ballena National Park, using 25 m2 quadrants, parallel to the coast, at seven sites. The ophiuroids were the most abundant group with 581 individuals and the asteroids the less abundant (48 individuals). Echinoderms densities were low, with the exception of the ophiuroids. Diversity, density and the number of groups were higher where sedimentation was lower. We suggest that sedimentation is having a negative effect on the diversity of echinoderms and on the development of the coral reefs in this park

Diversidad y abundancia de equinodermos en la laguna arrecifal del Parque Nacional Cahuita, Caribe de Costa Rica / Diversity and abundance of echinoderms from the reef lagoon at Cahuita National Park, Caribbean from Costa Rica

A total of 15 species of echinoderms (one asteroid, seven ophiuroids, five echinoids and two holothurians) were recorded at the Cahuita National Park reef lagoon, between September and October 2003, using a 1 m2 quadrant. The sites with coral substrate and algae were the most diverse, while those with seagrass and sand were the least. Ophiuroids were the most abundant group with 170 individuals, asteroids were the least abundant. Adding other studies and reports of echinoderms to this study, a total of 23 species have been found at Cahuita National Park, which is the most diverse area on the Caribbean of Costa Rica. We report nine new echinoderm records for Costa Rica's Caribbean.

Recuperacion de agar-agar a partir de medios de cultivo usados. / The agar-agar recovery from used culture media

En el presente trabajo se describen metodos para la recuperacion de agar a partir de medios de cultivo usados. Los metodos fueron valores a traves de los siguientes parametros: fuerza de gelificacion, temperatura de fusion, temperatura de gelificacion y porcentaje de recuperacion. Se encontro muy poca variacion en cuanto a la temperatura de fusion y de gelificacion del agar antes de ser utilizado y posterior a los tratamientos de recuperacion.Los rendimientos de los metodos fueron de un 92.8 por ciento para Mac Conckey 65 por ciento para agar sangre y un 78 por ciento de recuperacion para el agar eosina-azul de metileno (Levine). Los metodos son sencillos y economicos y su alto rendimiento justifica el proceso de recuperacion