Genetic differentiation among congeneric acanthocephalans in the yellow-bellied slider turtle

Aho, J. M.; Mulvey, M.; Jacobson, K. C.; Esch, G. W.

Allozyme variation in Neoechinorhynchus was used to examine the hypothesis that the occurrence of a single morphologically variable species may account for the observation of overlapping distributional patterns within the intestine of the yellow-bellied slider turtle (Trachemys scripta). Genetic analysis of 6 enzyme loci excluded the single species hypothesis and was consistent with the occurrence of 4 congeneric species within the turtle population. Discriminant analysis of multilocus genotypes, however, indicated that species designation based primarily on female body and egg morphology may not be error free. Individual turtles may harbor worms of a given species that are genetically different. Genetic variation on this scale may cause confusion in studies of helminth population and community structure. Subtle differences in species composition and distribution have the potential to confound community analyses, and further studies are needed to examine patterns in molecular-morphological taxonomic congruence.