There is evidence for introgression between the malaria vectors Anopheles g
ambiae and Anopheles arabiensis, which belong to the Anopheles gambiae comp
lex. Here we consider their relationship to another member of the complex,
Anopheles bwambae. Species identifications were made using rDNA-PCR and rev
ealed one An. bwambae/gambiae hybrid among 459 wild-caught mosquitoes. A 23
7-nucleotide region of the mitochondrial ND5 gene was sequenced in sixty-ni
ne individuals. The results suggest that there is an An. bwambae specific g
roup of haplotypes. However, two An. bwambae individuals carried haplotypes
typical of An. gambiae and An. arabiensis. This is the first evidence for
introgression between An. bwambae and other species of the An. gambiae comp
lex and suggests that introgression may be more widespread, also occurring
between other members of the complex.