Meeting Abstract
Caenorhabditis nematodes are abundant, globally distributed animals. Although C. elegans is one of the best studied organisms in biology, basic features of Caenorhabditis biodiversity and biogeography are poorly characterized. We isolated nematodes from more than 300 substrates (rotting fruit and flowers) collected on Barro Colorado Island, Panama, to discover the baseline characteristics of the local Caenorhabditis fauna. We identified Caenorhabditis worms morphologically and performed experimental mating tests with known strains in the laboratory to determine species identities. The majority of isolates were C. briggsae and C. tropicalis, two species with androdioecious mating systems (males and hermaphrodites). These two species are globally distributed. The remaining isolates belong to three species of Caenorhabditis with gonochoristic mating systems (males and females). Two of these, C. becei and C. panamensis, are known only from Panama. Species were not restricted to particular substrate types. Our results are consistent with emerging patterns in Caenorhabditis biogeography, which show that androdioecious species are cosmopolitan while gonochoristic species often have narrow geographic distributions.
