A phylogenetic study of the Anopheles punctulatus group of malaria vectorscomparing rDNA sequence alignments derived from the mitochondrial and nuclear small ribosomal subunits

A phylogenetic study of the members of the Anopheles punctulatus group was performed using structural and similarity-based DNA sequence alignments of the small ribosomal subunit (SSU) from both the nuclear and the mitochondri al genomes. The mitochondrial SSU gene (12S, similar to 650 bp) proved to b e highly restricted by its secondary structure and displayed little informa tive sequence variation. Consequently, it was considered unsuitable for a p hylogenetic study of these closely related mosquito species. A structural a lignment of the nuclear ribosomal DNA SSU (18S, similar to 2000 bp) proved to be more informative than similarity-based alignments. Analyses showed th e A. punctulatus group to be monophyletic with two major clades; a Farauti clade containing members displaying an all-black-scaled proboscis (A. farau ti 1-3 and 5-7) and the Punctulatus clade containing members displaying ext ensive white scaling on the apical half of the proboscis (A. farauti 4, A. punctulatus, and An. sp. near punctulatus). Anopheles koliensis was positio ned basal to the Farauti clade. (C) 2000 Academic Press.