Latitudinal variation in the reproductive cycle of two bivalves with contrasting biogeographical origin along the Humboldt Current Upwelling Ecosystem

摘要: Argopecten purpuratus (Lamarck, 1819) and Mesodesma donacium 1818) are bivalves that inhabit the Humboldt Current Upwelling Ecosystem. They have contrasting biogeographical origins, suggesting their responses to exogenous factors should differ. Using circular statistics, we examine synchrony/asynchrony in reproductive cycle between populations of each species. The results indicate there is asynchrony both species along distributional range. However, was synchrony for A. several location-pairs, including Paita-Chimbote, Chimbote-Callao, Callao-Pisco Pisco-Antofagasta. For M. , were only two synchronic groups: Camana-Capellania-Mehuin Hornitos-Penuelas-Longotoma-La Ligua-Cucao-Quilanlar. showed gametogenenic activity throughout year. In contrast, strong seasonality, with gametogenesis winter spawning spring/summer. conclusion, patterns observed these sympatric suggest on a large scale cycles follow expected biogeographic origin species, so it could be argued they modulated by endogenous factors. at local scale, show variation, likely determined oceanographic or hydrographic processes.