As part of a larger comparative study, marine nematode hard-bottom assemblages from Trinidad and Tobago were surveyed using artificial substrates. The collectors
(nylon pan scourers) were used as a standard substratum for the colonization by marine nematodes inhabiting subtidal hard, rocky bottom substrata. The artificial substrate units (ASUs) were deployed at four sites off the islands of Trinidad and Tobago, the former being the southernmost of the Caribbean chain of islands. The nematode fauna was represented by 5 orders, 25 families, 52 genera, and 70 species.
The Chromadoridae were most abundant followed by the Cyatholaimidae. At the family level, the nematode fauna was found to be similar to other temperate and tropical locations including those of a few previously described Caribbean assemblages.
Epigrowth feeders were dominant (65.2%) on the substrate followed by non-selective deposit-feeders (13.3%). Free-living marine nematodes of the western and southern Caribbean are not well known, while nematode fauna of hard-bottom substrates are even less known. This survey provides first records of the hard-bottom
nematode fauna of Trinidad and Tobago and also adds new evidence for the geographic range of some nematode species.