Evidence for genetic structuring and limited dispersal ability in the Great Barrier Reef sponge Carteriospongia foliascens

Understanding connectivity patterns for coral reef organisms is important for their effective management. Despite sponges being an important component of the benthic fauna on the Great Barrier Reef (GBR), there is limited information describing the scale at which populations are connected. Fourteen novel microsatellite markers were isolated for the common GBR sponge Carteriospongia foliascens, and population structure was compared between two locations separated by approximately 100 km (Davies Reef and Fantome Island). All loci were polymorphic at Davies Reef, but two were monomorphic at Fantome Island. F-statistics and clustering analyses revealed differentiation between the two sites. One pair of clones was also identified, suggesting this species can undergo asexual reproduction. Our results suggest restricted genetic connectivity, limited dispersal and therefore potentially high levels of self-recruitment for C. foliascens on the GBR.