Present address: School of Biological Sciences, University of Auckland, 3 A Symonds Street, PB 92019, Auckland 1142, New Zealand.
Do mosquitoes filter the access of Plasmodium cytochrome b lineages to an avian host?
Article first published online: 18 APR 2008
© 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd
Volume 17, Issue 10, pages 2552–2561, May 2008
How to Cite
GAGER, A. B., DEL ROSARIO LOAIZA, J., DEARBORN, D. C. and BERMINGHAM, E. (2008), Do mosquitoes filter the access of Plasmodium cytochrome b lineages to an avian host?. Molecular Ecology, 17: 2552–2561. doi: 10.1111/j.1365-294X.2008.03764.x
- Issue published online: 22 APR 2008
- Article first published online: 18 APR 2008
- Received 2 December 2007; revision received 8 March 2008; accepted 13 March 2008
- access filter;
- avian malaria;
- host shift;
- host-parasite coevolution;
- life cycle;
- parasite diversity
Many parasites show fidelity to a set of hosts in ecological time but not evolutionary time and the determinants of this pattern are poorly understood. Malarial parasites use vertebrate hosts for the asexual stage of their life cycle but use Dipteran hosts for the sexual stage. Despite the potential evolutionary importance of Dipteran hosts, little is known of their role in determining a parasite's access to vertebrate hosts. Here, we use an avian malarial system in Panama to explore whether mosquitoes act as an access filter that limits the range of vertebrate hosts used by particular parasite lineages. We amplified and sequenced Plasmodium mitochondrial DNA (mtDNA) from Turdus grayi (clay-coloured robin) and from mosquitoes at the same study site. We trapped and identified to species 123 141 female mosquitoes and completed polymerase chain reaction (PCR) screening for Plasmodium parasites in 435 pools of 20 mosquitoes per pool (8700 individuals total) spanning the 11 most common mosquito species. Our primers amplified nine Plasmodium lineages, whose sequences differed by 1.72%–10.0%. Phylogenetic analyses revealed partial clustering of lineages that co-occurred in mosquito hosts. However PAN3 and PAN6, the two primary parasite lineages of T. grayi, exhibited sequence divergence of 8.59% and did not cluster in the phylogeny. We detected these two lineages exclusively in mosquitoes from different genera — PAN3 was found only in Culex (Melanoconion) ocossa, and PAN6 was found only in Aedeomyia squamipennis. Furthermore, each of these two parasite lineages co-occurred in mosquitoes with other Plasmodium lineages that were not found in the vertebrate host T. grayi. Together, this evidence suggests that parasite–mosquito associations do not restrict the access of parasites to birds but instead may actually facilitate the switching of vertebrate hosts that occurs over evolutionary time.