Cryptic Bryozoa, leeward fringing reef of Bonaire, Netherlands Antilles, and their paleoecological application

A collection of 6151 bryozoan colonies (2 cyclostome species from 2 families, and 73 cheilostome species from 30 families) from the leeward fringing reef of Bonaire, Netherlands Antilles, is largely, but not entirely, of Caribbean affinities, with some links to Indo-Pacific populations. The bryozoans from Bonaire show some relation to water depth at species and higher taxonomic levels. Many of the species are found through all or most of the 73m depth range sampled. At a higher taxonomic level, some families include wide depth-ranging species, shallow-water species, and deep-water species. Several calculated diversity indices show variable trends with increasing water depth, with at most only slight increases with depth. The bryozoans in this S Caribbean reef assemblage do not show the well-defined depth zonation of corals. However, the recognition of deep- and shallow-water assemblages containing diagnostic species does show that cryptic reef-dwelling bryozoans have paleoecological utility as depth indicators in ancient reefs