Molecular Phylogeny of Rhus Gall Aphids (Hemiptera: Aphididae: Pemphiginae) Based on DNA Sequences
|Keywords||Gall aphid DNA sequence mtDNA gene EF- 1α gene Phylogenetic|
The Rhus gall aphids of the subtribe Melaphidina (Hemiptera: Aphididae:Pemphiginae), are a unique aphid group which parasitizes exclusively on the leaves of the primary host-plant Rhus to form galls. To complete their life cycle, it is necessary for this group of aphids to shift hosts between the primary (summer) hosts Rhus species and the secondary (winter) hosts mosses. The current classification system of Rhus gall aphids is mainly depends on morphology of aphids and galls, and their host plants. We examined the evolutionary relationships within the subtribe Melaphidina using sequences of the mitochondrial cytochrome C oxidase unitⅠ(COⅠ),Ⅱ(COⅡ), and cytochrome b (Cyt b) genes, and the nuclear elongation factor lα(EF-la) gene, with the sampling of nine species and three subspecies representing all six genera of Melaphidina. We obtained totally 3298bp of DNA sequence, including 1202bp of COⅠ、853bp of tRNA/COⅡ、433bp of Cyt b and 810bp of EF-1α, respectively. Phylogenetic trees of single and combined gene were constructed by MP, ML and BI methods. The results are as following:1, The Rhus gall aphids are showed to be monophyletic, six genera of Rhus gall aphids formed six well-supported clades, which supported the results of traditional morphological classification.2, Nurudea ibofushi is nested within the genus Schlechtendalia with high boot-strap value. In addition, gall shapes between N. ibofushi and other two species in Nurudea are quite different, but similar to the genus Schlechtendalia. So the species N. ibofushi should belong to the genus Schlechtendalia.3, The North American species Melaphis rhois is nested within the Asian species, which indicates that this species may originate from Asia.4, In case of the relationship between the subspecies of the genus Kaburagia, our results showed that K. rhusicola ovogallis is close to K. rhusicola, and then clustered with the other two subspecies K. rhusicola ensigallis and K. rhusicola ovatirhusicola. The monophyly of this genus Kaburagia was strongly supported with high boot-strap values.5, The cluster between genera are parallel with rather low boot-strap value, which indicates that the relationships between genera are still unsolved.