Resumen de Cryptofaunal Polychaetes from Oceanic and Continental Reefs in Venezuela
Patricia V. Fernández, David Bone, Carmen Rodríguez
Here we report on the biological diversity of the cryptofauna associated with dead coral fragments of Montastraea annularis (Ellis and Solander, 1786), comparing these between coral reefs from continental and oceanic regions. Dead fragments were taken from coral colonies at two depths at each locality, and the associated fauna were extracted and identified to taxonomic group. Polychaetes were separated by family, and by species for the most common family (Eunicidae) identified. The cryptofauna from both regions were mainly composed of polychaetes, sipunculids, and crustaceans. Polychaetes were the most abundant at the continental sites and sipunculids at the oceanic sites. A significantly higher diversity and density of cryptofauna were found at the continental region. Likewise, at the level of polychaete family, results also showed a clear spatial pattern: higher abundance and diversity at continental reefs. In total, 26 families of polychaetes were distinguished: 14 were common to both regions, three were exclusive to the oceanic reefs, and nine were exclusive to the continental regions. Eunicidae was the family with the highest percentage of individuals at both regions. Other important families were Sabellidae, Syllidae, and Nereididae. From the 17 eunicid species reported, eight belonged to the oceanic region, with Lysidice ninetta Audouin and Milne-Edwards, 1833 the most abundant, and 11 to the continental region, with Eunice cariboea Grube, 1856, Marphysa longula Ehlers, 1887, Marphysa cf longula, and L. ninetta as dominants. Significantly higher densities in continental reefs relative to oceanic reefs regardless of the level of taxonomic resolution may reflect reduced coral density or higher substrata availability at continental reefs.
