Unusual Morphotypes of the Giant Barrel Sponge off the Coast of Barbados

Giant barrel sponges (GBSs) belong to a cryptic species complex (Xestospongia spp.) and are found on tropical reefs worldwide. Over their range, including most of the Caribbean, GBSs have cylindrical shape, with variation in height, diameter surface complexity. However, off southwest coast Barbados, mostly exhibit clam shape or tub interspersed few that normal morphotype, suggesting this is not due environmental factors. Haplotype identification (mtDNA-COI) six indicated no clear genetic differentiation based morphotype; hence, morphological remains unexplained.