Parasitic infections of anurans from an urbanized rainforest biotope in Diobu, Port Harcourt, Nigeria

Abstract

The parasitic infections of anurans in an urbanized rainforest biotope in the Diobu, Port Harcourt area of Rivers State were investigated. The few anuran species encountered included Afrixalus fulvovittatus, Amietophrynus regularis, A. cameroonensis, Hyperolius concolor phase B, Hyperolius concolor phase C, Hoplobatrachus occipitalis, Phrynobatrachus sp., Ptychadena mascareniensis and Plychadena pumilio. Overall prevalence parasite prevalence in the anurans investigated was 67.4%. The ten parasite species recovered consisted of a pentastomid (Raillietiella sp), one cestode (Cylindrotaenia jaegerskioeldi), one monogenean (Polystoma pricei), two digeneans (Diplodiscus fiscthalicus and Mesocoelium monodi) and four nematode species (Cosmocerca ornata, Chabaudus leberrei, Amplicaecum africanum and a Rhabdias sp.). Unusual infection patterns were observed in some of the parasites encountered in this altered environment. The cystacanths of the acanthocephalan encountered occurred in aggregations with as many as 70 larvae occurring in cysts recovered from P. pumilio. This is possibly a parasitic adaptation to ensure effective delivery of infective stages in an unstable environment. The high (66.7%) prevalence of C. jaegerskioeldi in A. fulvovittatus is also unusual. We attribute this to an increase in the population of the intermediate hosts (beetles) occasioned by habitat alteration. The high prevalence of C. leberrei in H. concolor is also presumed to be related to the abundance of mosquito vectors in the study area. We concluded that habitat alteration not only reduces anuran species diversity, but can also alter the transmission dynamics of some parasites in the altered environment.

Keywords: Anurans; parasites; rainforest; urabnizations; Nigeria