ASCOMYCETOUS YEAST COMMUNITIES OF MARINE-INVERTEBRATES IN A SOUTHEASTBRAZILIAN MANGROVE ECOSYSTEM

The ascomycetous yeast communities associated with 3 bivalve mollusk, and 4 crab species were studied in the mangrove at Coroa Grande on Sep etiba Bay in Rio de Janeiro, Brazil. These were made up mostly of dive rse but sparse and apparently allochtonous yeast populations. The stri king exception was a prevalent population of the species Kluyveromyces aestuarii, which predominated the yeast communities of 2 detritus fee ding crabs, Sesarma rectum and Uca spp., and the shipworm Neoteredo re ynei. However, K. aestuarii was absent from the omnivorous crabs Aratu s pisonii and Goniopsis cruentata, and the clam Anomalocardia brasilia na, and was rare in the clam Tagelus plebeius from mostly submerged mo re sandy sediments. Pichia membranaefaciens, Candida valida-like, Cand ida krusei, Candida sorbosa, Candida colliculosa-like, Candida famata- like, Kloeckera spp., Candida guilliermondii, Candida albicans, Candid a silvae, Geotrichum spp., Rhodotorula spp., Cryptococcus spp., and th e methylotrophic yeast Candida boidinii were frequently isolated. The 322 ascomycetous yeast cultures representing 252 isolates from crabs a nd mollusks were classified as 40 species that fit standard descriptio ns, and 44 putative new species. The ascomycetous yeast communities of the mangrove ecosystem include many new biotypes that require better taxonomic definition.