Habitat preferences and species associations of shallow-water marine Tubificidae (Oligochaeta) from the barrier reef ecosystems off Belize, Central America

Abstract

The marine tubificid oligochaete fauna of Belize is the most diverse that has been described for the Caribbean Sea, with records for over 50% of all known Caribbean species. Tubificids were sampled at 77 stations around the outer barrier of the coral reefs off the Belize mainland. A total of 1,529 individuals representing 52 species were collected. Species distribution patterns were controlled mainly by sediment type and the presence or absence of mangroves. Six species (Phallodrilus molestus, Tubificoides bermudae, Inanidrilus leukodermatus, Heterodrilus flexuosus, Bathydrilus formosus, Smithsonidrilus hummelincki) with diverse life history characteristics were common and had broad habitat preferences being found in various types of heterogeneous sandy sediments. Heterodrilus flexuosus was the only common species in these samples known only in Belize. The other five common species range from Belize to Florida or Bermuda. Most other species have narrower habitat preferences and are limited to specific habitats. For example, one group of gutless species was restricted to organically enriched fine to medium sands, a group of Limnodriloidinae occurred only in mud around mangrove cays, and a group of meiofaunal species were restricted to saline groundwater.