HELMINTH COMMUNITY STRUCTURE IN SEVEN SPECIES OF TADPOLES FROM NEBRASKA Heather Tracy and Matthew Bolek, Department of

1. A B C D E F G Figure 2. A) Rana catesbeiana, N = 28, B) Rana blairi, N = 47, C) Rana pipiens, N = 40, D) Hyla chrysoscelis, N = 32, E) Pseudacris maculata, N = 15, F) Bufo woodhousii, N = 85, G) Spea bombifrons, N = 10. A B C D Figure 3. A) Gorgoderina attenuata, unencysted worm in kidney. B) Gorgoderina attenuata removed from kidney. C) Echinostome metacercaria in kidneys. D) Glypthelmins pennsylvaniensis unencysted metacercaria in tissue and body cavity. E) Plagiorchiid metacercaria in tissue. F) Spyroxis sp. encysted in stomach. G) Gyrinicola batrachiensis, large intestine. H) Eggs of Gyrinicola batrachiensis. E F G H HELMINTH COMMUNITY STRUCTURE IN SEVEN SPECIES OF TADPOLES FROM NEBRASKA Heather Tracy and Matthew Bolek, Department of Zoology, Oklahoma StateUniversity Abstract Larval anurans, specifically tadpoles, are a group of hosts that have been ignored in helminth community studies. Tadpoles differ from their adult anuran counterparts in many ways, both ecologically and physiologically and therefore, should differ in their helminth community structure from adult anurans. We examined 257 tadpoles of 7 species during May-August 2008, form Nebraska for helminth parasites. The helminth compound community of this larval amphibian assemblage consisted of 6 species and was dominated with larval trematodes. There was a high degree of helminth species overlap among sympatric tadpole species, with only a single larval trematode, Glypthelmins pennsylvaniensis, being restricted to a single tadpole species. Overall helminth prevalence and mean species richness was highest in bullfrog tadpoles (Rana catesbeiana) and lowest in the plains spadefoot toads (Spea bombifrons) and this was related to time spent in the pond through metamorphosis being 104-156 wks for bullfrog tadpoles and 2-3 wks for spadefoot tadpoles. Results A total of 3,344 helminths of 6 species were recovered (Fig. 3). The helminth compound community of tadpoles was dominated by trematode metacercarial stages (N = 3,043), followed by adult nematodes (N = 250), and juvenile nematodes and adult non-gravid trematodes (N = 44; Fig. 4). Overall prevalence and mean species richness varied among the different species of tadpoles, being highest for Rana catesbeiana and lowest for Spea bombifrons (Fig. 4). Figure 1: Frog life cycle. All temperate tadpoles are aquatic during development, and contained into a single body of water. During this time intestine length, mouth shape and body form changes. After metamorphosis, adults are able to move about freely. Figure 4. A) Overall prevalence of helminths recovered in 7 species of tadpoles. B) Average species richness in 7 species of tadpoles. Conclusion Tadpole helminth communities are depauparate, and dominated by generalist larval trematodes acquired through skin penetration. Only 1 species was considered host specific, Glypthelmins pennsylvaniensis. Only 1 species was considered to have stadial specificity in tadpoles, Gyrinicola batraciensis. Materials and Methods Seven species of tadpoles (Fig. 2) were collected from 5 different locations in Eastern and Western Nebraska and examined for helminth parasites. Tadpoles were collected by dip-net brought back to the laboratory, euthanized, and all organs including the musculature were examined, and all parasites were identified as specifically as possible. Standard measures of community structure were calculated. Acknowledgements Thanks to Research Services Council and BRIN at the University of Nebraska-Kearney for funding this project, and also Morgan Tracy for helping with tadpole collections.