ABSTRACT
Three species of paxillosid starfishes (Astropecten brasiliensis, A. cingulatus and Luidla ludwigi scotti) were sampled monthly at Cabo Frio (23°S; 42°W) during 1987. The allometric relationship between arm length (radius) and wet weight for A. brasiliensis and A. cingulatus are similar and differ from L. ludwigi scotti which has a smaller increase in biomass with an increase in length. The relationship between starfish size and the cumber of prey ingested was linear with weight but not with length: the higher the biomass, the larger the number of prey ingested. A similar interspecific relation is not found when mean prey size data were analysed. Studies on the feeding ecology of starfishes should use weight as the body-size measurement.
