| Summary: | The <i>Scaptodrosophila</i> represent a diverse group of <i>Diptera</i> closely related to <i>Drosophila.</i> Although they have radiated extensively in Australia, they have been the focus of few studies. Here, we characterized the karyotypes of 12 <i>Scaptodrosophila</i> species from several species groups and showed that they have undergone similar types of karyotypic change to those seen in <i>Drosophila</i>. This includes heterochromatin amplification involved in length changes of the sex and ‘dot’ chromosomes as well as the autosomes, particularly in the <i>coracina</i> group of species. Numerous weak points along the arms of the polytene chromosomes suggest the presence of internal repetitive sequence DNA, but these regions did not C-band in mitotic chromosomes, and their analysis will depend on DNA sequencing. The nucleolar organizing regions (NORs) are at the same chromosome positions in <i>Scaptodrosophila</i> as in <i>Drosophila,</i> and the various mechanisms responsible for changing arm configurations also appear to be the same. These chromosomal studies provide a complementary resource to other investigations of this group, with several species currently being sequenced.
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