Three forms of Sitobion Mordvilko occur commonly on grasses in southern Australia. S. nr fragariae (Walker), collected in Tasmania, Victoria, New South Wales, South Australia and Western Australia, has a diploid chromosome number of 18, and differs in electrophoretic mobility of enzymes at several loci from S. miscanthi (Takahashi), also with 2n = 18. A third form is here regarded as being derived from S. miscanthi, but differs from it in enzyme mobility at 2 loci and has 2n = 17, apparently resulting from an autosomal fusion. A fourth form, with 2n = 20, has been collected in the Sydney region on 2 occasions. It is electrophoretically identical to the 2n = 17 form. The 2n = 17 and 2n = 20 forms are concluded to be chromosomal races of S. miscanthi. The seasonal distribution of all forms is recorded; S. nr fragariae is common in spring, S. miscanthi (2n = 18) has been collected only in November‐December, and S. miscanthi (2n = 17,20) in November‐December and March‐July. This suggests different environmental tolerances for the 3 major forms.
|Number of pages||7|
|Journal||Australian Journal of Entomology|
|Publication status||Published - 1990|