Meeting Abstract

52.3  Tuesday, Jan. 5  Examining genetic variation of the Acanthocephalan Profilicollis altmani parasitizing mole crabs (Emerita spp.) in North America GOULDING, T*; COHEN, S; Romberg Tiburon Center for Environmental Studies, San Francisco State University; Romberg Tiburon Center for Environmental Studies, San Francisco State University tc.goulding@yahoo.com

Parasites are often an overlooked component of marine ecosystems despite their abundance and importance in food webs. This is especially true of acanthocephalans or “spiny-headed worms”, a small phylum (~1150 species) of parasitic worms that can infect a variety of hosts from marine, freshwater and terrestrial habitats. Mole crabs (Emerita spp.), found in the intertidal zone of sandy beaches around North America, serve as the intermediate host for the acanthocephalan Profilicollis altmani which develops in their hindgut. Although P. altmani is abundant in host populations, the conserved morphology of acanthocephalans can confound species identification. Using genetic techniques, we compare different populations of P. altmani to determine if morphologically cryptic species are present. In this study, multiple species of mole crabs were collected from the Pacific and Atlantic Coasts, as well as the Gulf of Mexico. DNA was extracted from the parasites and two loci were sequenced: the Internal Transcribed Spacer (ITS) and Cytochrome Oxidase Subunit I (CO1). Analysis showed that ITS was not variable between populations of P. altmani, so a phylogeny was constructed using Bayesian analysis of CO1. This phylogeny shows that genetic variation among the parasite P. altmani from different Emerita spp. is low, potentially the result of long-range dispersal of their eggs between populations by birds and ocean currents.