Abstract

The queen conch is a resource of ecological and economical importance in the Caribbean that suffered a widespread reduction of its populations. Aldana Aranda (2008) reported an intense and generalized sporozoan infection in the digestive gland of Strombus gigas. This study reports the occurrence of a Coccidian (Apicomplexa) infecting the digestive gland of conchs in the Florida Keys in two locations: offshore, where conch reproduction is common (Pelican Shoal, Eastern Sambo), and nearshore where reproduction has ceased relatively recently (East Sisters Rock, Tingler Island). Incidences of Apicomplexa in the digestive gland for conchs collected in June and February and compared the occurrence of parasites with gonadal development between conch found offshore and those found nearshore, were realized. The results showed that the Apicomplexa was present in the digestive gland of conchs in every locality sampled; conchs offshore and conchs nearshore were parasitized. Conchs from East Sisters Rock (near shore, June) and Eastern Sambo (offshore, June) had the highest incidence of infection with an average of 32.34 and 30.35 parasites, respectively; Pelican Shoal (offshore, february) and Tingler Island (near shore, february) had an average of 22.0 and 18.38 parasites, respectively. No correlation was found between number of parasites and gonadal development with Canonical Variate Analysis. Test of significance of first canonical axis: eigenvalue = 0.200, F-ratio = 87.160, P-value = 0.0020. These results raise questions: What are the environmental factors influencing this infection. What is the correlation between this parasite and gonad development. Are conchs the definitive host or do they serve as an intermediate host?

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