, Volume 209, Issue 2, pp 141-153

First online:

Freshwater snails of São Tomé, with special reference to Bulinus forskalii (Ehrenberg), host of Schistosoma intercalatum

  • D. S. BrownAffiliated withDepartment of Zoology, British Museum (Natural History)

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São Tomé Island has 3 known taxa of freshwater gastropod, here identified to species for the first time; Neritina afra Sowerby, Ferrissia eburnensis Binder and a distinctive form of Bulinus forskalii (Ehrenberg). The Bulinus acts as intermediate host for the parasite Schistosoma intercalatum Fisher, the cause of human schistosomiasis in foci of infection detected in recent years on São Tomé. A morphological characterization of this snail is presented, in respect of the shell, radula and copulatory organ. It is compared with B. forskalii populations sampled on the African mainland (Nigeria, Cameroon, Gabon and Angola) and with related taxa. Despite differences in the shell from the commonly found form of B. forskalii it seems appropriate to identify the São Tomé population as an extreme conchological variant of this taxon.

Key words

Bulinus Schistosoma intercalatum Africa São Tomé taxonomy schistosomiasis