GULF OF GUINEA ISLANDS' BIODIVERSITY
NETWORK
Cytotaxonomy, morphology and molecular systematics of the Bioko form of Simulium yahense (Diptera:Simuliidae)
R. J. Post 1, P. K. Flook 2, A. L. Millest 3,
R. A. Cheke 4, P. J. McCall 2, M. D. Wilson 5,
M. Mustapha 1, S. Somiari 6, J. B. Davies 2,
R. A. Mank 7, P. Geenen 7, P. Enyong 8, A. Sima
9 and J. Mas 10.
1 Department of Entomology, The Natural History Museum, Cromwell Road,
London, SW7 5BD, UK. E-mail: R.Post@nhm.ac.uk
2 Division of Parasite and Vector Biology,
Liverpool School of Tropical Medicine, UK
3 Department of Biological Sciences, University of Salford, UK
4 Natural Resources Institute, University of Greenwich, Chatham, UK
5 Noguchi Memorial Institute for Medical Research, University of Ghana,Ghana
6 Windber Research Institute, Windber, USA
7 Animal Taxonomy Section, Wageningen University,
The Netherlands
8 Medical Research Station, Kumba, Cameroon
9 Onchocerciasis Control Programme, Ministry of Health, Malabo, Equatorial
Guinea
10 Onchocerciasis Control Programme, Spanish International Cooperation Agency
Malabo, Equatorial Guinea
Bulletin of Entomological Research (2003) 93: 145 –157
Abstract
Cytotaxonomic analysis of the polytene chromosomes from larvae of the Simulium damnosum Theobald complex from the island of Bioko in Equatorial Guinea is reported,and a new endemic cytoform is described.Chromosomally this cytoform is close to both S.squamosum (Enderlein)and S.yahense Vajime &Dunbar, but is not identical to either.However,it is morphologically and enzymatically identical to S.yahense .The Bioko form was also found to differ from other cytoforms of the S.damnosum complex in West Africa in the copy number or RFLP pattern of several different repetitive DNA sequences.It is clear that the Bioko form is genetically distinct from other populations of the S.damnosum complex, and whilst it is closest to S.yahense ,it shows features that suggest a high degree of geographical and genetic isolation.Such isolation is an important consideration in the assessment of the potential for onchocerciasis vector eradication on Bioko.