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Hydrobiologia

, Volume 317, Issue 2, pp 127–139 | Cite as

The freshwater snail Bulinus tropicus (Planorbidae) in Namibia, characterised according to chromosome number, enzymes and morphology

  • D. S. Brown
  • B. A. Curtis
  • D. Rollinson
Article

Abstract

Freshwater snails collected in central Namibia, south-western Africa, from 15 populations belonging to the Bulinus truncatus/tropicus complex (Planorbidae) are characterised in respect of their chromosome number, morphology, egg proteins and enzymes. The population samples were all consistently diploid and euphallic. The findings are compared with observations on this group of snails in other areas of Africa. It is concluded that the Namibian populations belong to a single species, B. tropicus (Krauss, 1848), of which B. parietalis (Mousson, 1887) is probably a synonym. No evidence was found of any occurrence of the tetraploid species B. truncatus or of snails belonging to the B. africanus group; lack of a potential intermediate host therefore precludes transmission of Schistosoma haematobium in this area.

Key words

Mollusca Bulinus freshwater snails taxonomy distribution Africa Namibia Schistosoma haematobium schistosomiasis 

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Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • D. S. Brown
    • 1
  • B. A. Curtis
    • 2
  • D. Rollinson
    • 1
  1. 1.Department of ZoologyThe Natural History MuseumLondonUK
  2. 2.State MuseumWindhoekNamibia

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