Shell Morphology of Three Medical Important Tropical Freshwater Pulmonate Snails from Five Sites in South-Western Nigeria

Biomphalaria pfeifferi, Bulinus globosus and Lymnaea natalensis act as obligatory vectors of schistosomiasis and fascioliasis in Sub-Saharan Africa. Although, they are known to be widely distributed throughout Nigeria, there is the need for precise species identification to help vector control initiatives. Snail shell morphometry has previously proved useful in taxonomic studies. We thus employed seven morphological parameters of snail shells in identifying three snail vectors from five water bodies in South-Western Nigeria. Snails were sampled for 14 months and total of 718 snails were collected, which include 204 B. pfeifferi, 316 B. globosus and 198 L. natalensis. Eleyele Lake had 278 snails which was the highest number followed by Osun River with 64 snails. Our finding revealed B. globosus as the dominant snail in all the five sites, while B. pfeifferi and L. natalensis were present in only three sites. The presence of the snails in otherwise uninfected water bodies may have implications for transmission and disease control in these areas. Our findings should prove useful for improved snail identification, information, which will be invaluable for vector control in affected communities.