CONVERGENCE OF MOLECULAR AND MORPHOLOGICAL DATA REVEALS PHYLOGENETIC INFORMATION ON TETRANYCHUS SPECIES AND ALLOWS THE RESTORATION OF THE GENUS AMPHITETRANYCHUS (ACARI, TETRANYCHIDAE)

Nucleotide sequence variation and morphological characters were used t o study the evolutionary relationships among nine tetranychid mites sp ecies. A phylogenetic study of this family based on mitochondrial cyto chrome oxidase subunit I (COI) sequences had previously placed the spe cies Tetranychus viennensis Zacher outside the other species analysed in the genus. Phylogenetic relations within the genus were re-examined with the addition of the species Tetranychus quercivorus Ehara & Goto h, which is morphologically close to T. viennensis. Another region of the genome, the second internal transcribed spacer (ITS2) of ribosomal DNA, was also studied and proved to be of considerable interest at th is taxonomic level. Both COI and ITS2 sequences indicated a close rela tionship between T. viennensis and T. quercivorus, which are grouped t ogether and distinct from the other Tetranychus examined. The two spec ies display morphological characteristics such as the absence of a med io-dorsal spur on all empodia of the legs of both sexes and the presen ce of anastomosing peritremes. This distinguishes them from the other members of the genus Tetranychus. The convergence of molecular and mor phological data suggests that T. viennensis and T. quercivorus should not be classified in the genus Tetranychus. It is proposed that the ge nus Amphitetranychus Oudemans should be restored for classification of these species. Finally, a key to the Tetranychini tribe genera with o ne pair of para-anal setae is presented.