Genus Onesia – Field Guide to the Insects of Tasmania

Onesia spp. – these are medium to small sized blowflies that often superficially resemble Lucilia species. Generally they have the thorax blackish with thin white dusting and the abdomen metallic green to blue, or coppery (in O. tibialis the abdomen is black with a shifting yellowish pruinosity). They lack the golden hairing seen in the larger golden blowfly Calliphora species. The presutural pairs of acrostichal bristles are placed in rows that are generally much closer to each other than what is seen in typical Calliphora. The wingvein M is usually rather straight after the bend, whereas in Calliphora this section is generally far more recurved (compare wings link). [Note, that Bellardia are currently not divided from Onesia in the Australian catalogue. The Tasmanian species more rightly fall into Bellardia in having only 2 post-sutural intra alar bristles, instead of 3 to 4 for Onesia.]