Use of the internal transcribed spacer (ITS-1) region to infer Orius (Hemiptera : Anthocoridae) species phylogeny

Partial 18S, 5.8S and the intervening internal transcribed spacer region 1 (ITS-1) of nuclear ribosomal DNA from representatives of 10 species of the genus Orius and one outgroup species (Wollastoniella rotunda Yasunaga et Mi yamoto) were analyzed by PCR and DNA sequencing. Within the taxa analyzed, the length of the ITS-1 region varied from 230-663 bp. Phylogenetic trees g enerated from informative sites within the sequences were highly resolved i n the proximal regions of the branches, but more ambiguous deeper within th e tree. Orius species relationships showed some agreement with anecdotal mo rphological observations and this study represents a first attempt in estab lishing Orius species relationships.