Preliminary results in the taxonomy of the cryptic Aphid frangulae/gossypii obtained from mitochondrial DNA sequence

Phylogenetic relationships within members of the cryptic group Aphis frangulae/gossypii (Rhynchota Aphididae) were inferred from partial sequence of mitochondrial cytochrome C oxidase (COI). Sixteen postulated species, with several specimens per species, were included, representing part of recognized species inside the group. Results show that the monophyly of the frangulae/gossypii group is well supported. In the phylogenetic tree the two main clusters represented by A. gossypii and A. frangulae are clearly evident, each one associated with other more strictly allied species. Inside the A. gossypii (sensu stricto) group there is very little if any genetic difference within other postulated species, i.e. A. sedi, A. catalpae, A. myopori, and A. capsellae; the latter might represent therefore populations of the former species rather than separate specific taxa in the traditional sense.