Transplant bioassay induces different imposex responses in two species of the genus

Abstract

A bioassay to study differential specific responses in imposex development due to marine organotin pollution was done bytransplanting specimens of the gastropodsStramonita haemastomaandStramonita rusticafrom an imposex-free area to amarina with high marine traffic inside a ship repair yard, a place where local populations ofS. haemastomawere known toshow high indices of imposex. Three hundred sexually mature, imposex-free specimens of each species were kept in cagesfor 120 days, and samples of 30 individuals were periodically analysed for imposex development. Shell length, penis lengthand vas deferens development were recorded and imposex development indices (% imposex, RPLI and VDSI) werecalculated. Our results indicated that imposex induction inS. haemastomais faster and more sensitive than inS. rustica.Imposex incidence inS. haemastomacould be a useful tool for monitoring marine pollution by organotin compounds inharbours along the Brazilian coasy