Helminth Community of Tree frogs at the Okomu National Park, Edo State, Nigeria
AbstractThe tree frogs of the Okomu National Park were investigated for their helminth parasitic infections. The 24 species of tree frogs encountered belonged to the families Arthroleptidae, Hyperoliidae, Ranidae and Rhacophoridae. The helminth parasites encountered in the study included: Cestoda: Baerietta sp. (7.4%); Monogenea: Polystoma chiromantis (4.7%), Polystoma dorsalis (3.7%), Polystoma gracei (6.7%) and Polystoma okomuensis (15.6%); The trematodes encountered included Mesocoelium monodi, Mesocoelium monas and Ostioloides rappiae which were observed to be multi-host parasites. Among the nematodes, Cosmocerca ornata and an unidentified oxyurid nematode were also observed to infect a wide range of hosts. The filariid, Foleyellides sp. was only recovered from Hyperolius fusciventris burtoni (6.8%). Some of the parasites found in this study including Polystoma chiromantis, Polystoma dorsalis, Polystoma gracei and Ostioloides rappiae are being reported for the first time in Nigeria, thus increasing their geographical range. A summary of the helminth community of the frogs investigated showed that the transmission strategies employed by the parasites varied. They included a one host life cycle among the monogeneans, trophical transmission among the cestodes and trematodes, vectoral transmission in the filariid Foleyellides sp. and the use of frogs as transport (paratenic) hosts by the larval ascaridoid and other encysted parasites occurring on organs of the viscera.
Keywords: Monogenea, Cestoda, Trematoda, Nematoda, Transmission strategy
Nigerian Journal of Parasitology, Vol. 33  March 2012, pp. 1-8