Species recognition of congeneric acanthocephalans in slider turtles by randomamplified polymorphic DNA (RAPD) markers

Species recognition of acanthocephalans of the genus Neoechinorhynchus (Hamann, 1892) found in the freshwater turtle Trachemys scripta (Wied, 1838) has previously been based primarily on female body and egg morphology. Observed morphological plasticity within and among species may lead to the misclassification of female specimens and leaves males of different species completely indistinguishable. Here, random-amplified polymorphic DNA (RAPD) analysis was used to genetically characterize samples of Neoechinorhynchus pseudemydis (Cable and Hopp, 1954), Neoechinorhynchus emydis (Leidy, 1851), and Neoechinorhynchus emyditoides (Fisher, 1960). Amplifications performed with 3 decamer oligonucleotides showed banding patterns with a few diagnostic fragments that allowed the recognition of N. pseudemydis specimens from those of the N. emydis-N. emyditoides group. No primer gave a species-specific locus that allowed the differentiation of N. emydis from N. emyditoides specimens, suggesting that they could belong to a sole taxon. The species assignment of females of uncertain classification and of males is fully reliable using RAPD markers. Thus, identification of acanthocephalan species by RAPD in the helminth infracommunities could potentially be very useful to determine community structure. RAPD and other polymerase chain reaction- based methods have some practical advantages over multilocus discriminant analysis, such as the ability to use ethanol-stored specimens and small tissue samples of parasites.