A SURVEY OF THE TAPEWORM FAUNA OF THE COWNOSE RAY, RHINOPTERA BONASUS, FROM THE NORTHERN GULF OF MEXICO WITH COMMENTS ON INTERMEDIATE HOSTS

Abstract

This survey determined the cestode diversity parasitizing the spiral intestine of the cownose ray, Rhinoptera bonasus (Mitchill), in the northern Gulf of Mexico. Twelve cownose rays were collected near barrier islands off Ocean Springs, Mississippi, U.S.A. Thirteen species were identified. Eight were previously known; and the geographic distribution of seven expanded to include the Gulf of Mexico. Duplicibothrium minutum is redescribed. Two species each of Duplicibothrium and Eniochobothrium and one Polypocephalus species are described. Nineteen species are now known to parasitize R. bonasus throughout its range. The coquina clam, Donax variabilis (Say), inhabiting the swash zones of the barrier islands that R. bonasus frequents, were examined for larval tapeworms. Examination of 915 clams collected revealed two types of larvae. These larvae were identified as Rhodobothrium paucitesticulare and D. minutum, parasitizing R. bonasus as adults, using morphology and molecular sequence data. Prevalence and intensity of adults and larvae are presented.