Curtiss 2023, Chaetorellia sp. spiracular hairs datafile

Abstract – Yellow starthistle, Centaurea solstitialis L. (Asterales: Asteraceae), has invaded over 8 million ha of the United States. The target of biological control since the 1950’s, six insect species were intentionally released, and one was accidentally introduced into North America. Two introduced Tephritidae, the yellow starthistle peacock fly, Chaetorellia australis Hering, and the false peacock fly, Chaetorellia succinea (Costa), attack C. solstitialis seedheads as immatures. Separation of the immature stages of these two immature flies in infested seedheads is difficult. In this study, the puparia of C. australis and C. succinea (Diptera: Tephritidae) were evaluated using scanning electron microscopy to assess morphological differences in these species. It was found that the branched spiracular hairs can be used diagnostically to separate these species: C. succinia has 5.91 ± 0.43 and C. australis has 2.67 ± 0.25 spiracular hair branches between posterior spiracles.