in our area, throughout US to so. Canada; 2 spp. are Neotropical and only reach so. FL, one has been eradicated (formerly widespread in so. US north to SC-IN-IA-c.CA), so C. macellaria is the only species one may expect to encounter(1)
two spp. cause myiasis and considered pests: C. hominivorax (Primary Screwworm, extirpated) and C. macellaria (Secondary Screwworm, widespread)(3)
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