Bulinus spp.

Diagnostic features

Shells medium sized, elongate to ovate, sinistrally coiled. High to moderately raised to low spire; with or without umbilicus, whorls rounded (Bulinus africanus)to bluntly shouldered sometimes bluntly carinate (Bulinus forskalii) with indented sutures. Aperture large, ovate. With or without columella twist.  Smooth or with periostracal spiral threads, nodules and setae. The protoconch is distinctly sculptured with spiral rows of punctae (a feature not seen in any Australian genera).

Animals have long slender tentacles and reddish blood that contains haemoglobin. Pseudobranch large, deeply folded and highly vascularised. Copulatory organ: the penis does not project freely into the penis sheath but is a long and coiled eversible tube attached at both the upper and lower end of the sheath. Praeputium present. Numerous prostatic lobes are concentrated into a compact organ. May have a ridge along the ventral surface of the kidney. No renal ridge. Mesocone of the first lateral tooth of the radula may be simple without cusps or with one or two lateral cusps either or on one side of the central cusp.

Classification

Bulinus O. F. Müller, 1781

Class Gastropoda

Infraclass Heterobranchia

Megaorder Hygrophila

Order Lymnaeida

Superfamily Planorboidea

Family Planorbidae

Subfamily: Bulininae

Genus Bulinus O. F. Müller, 1781 (Type species: Bulinus senegalensis Müller, 1781) (Synonyms - see http://www.marinespecies.org/aphia.php?p=taxdetails&id=224352).

Original reference: Müller O. F. (1781). Geschichte der Perlen-Blasen. Der Naturforscher 15: 1-20, Tab. I.

Type locality: Podor,Senegal, West Africa.

State of taxonomy

We follow Brown (2002)

Biology and ecology

On water weeds etc., in ponds, lakes, swamps and sluggish streams and rivers. Some capable of aestivation. Development direct.

Several species are important intermediate hosts of human diseases (see Notes).

Distribution

Widespread in Africa, islands of the Indian Ocean, Spain, Sicily and the Middle East.

Notes

This genus does not occur in Australia but is mentioned here as there is the possibility it could be accidentally introduced with potential serious consequences.

Bulinus africanus (Krauss, 1848) is an intermediate host of Schistosoma haematobium that causes schistosomiasis in humans and S. mattheei that causes bovine schistosomiasis. Schistosomiasis is a disease that affects the health of millions of people, as well as their livestock in Southern Africa. Bulinus africanus can also play a role in the transmission of cercarial dermatitis (swimmer’s itch) (de Kock and Wolmarans 2005).

Bulinus forskalii (Ehrenberg, 1831) is an intermediate host for the parasites Schistosoma guineensis, Schistosoma intercalatum, Schistosoma haematobium, Gastrodiscus aegyptiacus and some other species of paramphistome trematodes that infect humans and stock.

Further reading

Albrecht, C., Kuhn, K. & Streit, B. (2007). A molecular phylogeny of Planorboidea (Gastropoda, Pulmonata): insights from enhanced taxon sampling. Zoologica Scripta 36: 27-39.

Albrecht, C., Stelbrink, B. & Clewing, C. (2019). Bulinidae P. Fischer & Crosse, 1880. Pp. 167-171 in C. Lydeard & Cummings, K. S. Freshwater Mollusks of the World: a Distribution Atlas. Baltimore, John Hopkins University Press.

Baker, F. C. (1945). The molluscan family Planorbidae. Urbana USA, University of Illinois Press.

Brown, D. S. (1991). Freshwater snails of São Tomé, with special reference to Bulinus forskalii (Ehrenberg), host of Schistosoma intercalatum. Hydrobiologia 209: 141-153.

Brown, D. S. (2002). Freshwater snails of Africa and their medical importance, CRC press.

Gow, J. L., Noble, L. R., Rollinson, D., Mimpfoundi, R. & Jones, C. S. (2004). Breeding system and demography shape population genetic structure across ecological and climatic zones in the African freshwater snail, Bulinus forskalii (Gastropoda, Pulmonata), intermediate host for schistosomes. Molecular Ecology 13: 3561-3573.

Gow, J. L., Noble, L. R., Rollinson, D. & Jones, C. S. (2005). A high incidence of clustered microsatellite mutations revealed by parent-offspring analysis in the African freshwater snail, Bulinus forskalii (Gastropoda, Pulmonata). Genetica 124: 77-83.

Hubendick, B. (1955). Phylogeny of the Planorbidae. Transactions of the Zoological Society of London 28: 453-542.

Jørgensen, A., Madsen, H., Nalugwa, A., Nyakaana, S., Rollinson, D., Stothard, J. R. & Kristensen, T. K. (2011). A molecular phylogenetic analysis of Bulinus (Gastropoda: Planorbidae) with conserved nuclear genes. Zoologica Scripta 40: 126-136.

Kane, R. A., Stothard, J. R., Emery, A. M. & Rollinson, D. (2008). Molecular characterization of freshwater snails in the genus Bulinus: a role for barcodes. Parasites and Vectors 1: 1-15.

de Kock, K. N. & Wolmarans, C. T. (2005a). Distribution and habitats of the Bulinus africanus species group, snail intermediate hosts of Schistosoma haematobium and S. mattheei in South Africa. Water SA 31: 117-125.

de Kock, K. N. & Wolmarans, C. T. (2005b). Distribution, habitats and role as intermediate host of the freshwater snail, Bulinus forskalii, in South Africa. Onderstepoort Journal of Vetinary Research 72: 165-174.

Labbo, R., Djibrilla, A., Zamanka, H., Garba, A. & Chippaux, J.-P. (2007). Bulinus forskalii: a new potential intermediate host for Schistosoma haematobium in Niger. Transactions of the Royal Society of Tropical Medicine and Hygiene 101: 847-848.

Lotfy, W. M., Brant, S. V., Ashmawy, K. I., Devkota, R., Mkoji, G. M. & Loker, E. S. (2010). A molecular approach for identification of paramphistomes from Africa and Asia. Veterinary Parasitology 174: 234-240.

Mandahl-Barth, G. (1965). The species of the genus Bulinus, intermediate hosts of Schistosoma. Bulletin of the World Health Organization 33: 33.

Nalugwa, A., Jørgensen, A., Nyakaana, S. & Kristensen, T. K. (2010). Molecular phylogeny of Bulinus (Gastropoda: Planorbidae) reveals the presence of three species complexes in the Albertine Rift freshwater bodies. International Journal of Genetics and Molecular Biology 2: 130-139.

Ng, T.H., Tan, S.K., Wong, W.H., Meier, R., Chan, S-Y., Tan, H.H. and Yeo, D.C.J. 2016. Molluscs for Sale: Assessment of Freshwater Gastropods and Bivalves in the Ornamental Pet Trade. PLOS One. DOI:10.1371/journal.pone.0161130.

Walker, J. C. (1988). Classification of Australian buliniform planorbids (Mollusca: Pulmonata). Records of the Australian Museum 40: 61-89.

Note: there is a vast literature on members of this genus, the above being only a small sample.