closely resembles the common housefly (Musca domestica) but has a broader abdomen and can be identified by four characteristic longitudinal stripes across the thorax + several dark dorsal spots on the abdomen. The proboscis is black, long, and thin.
larvae & pupae have uniquely shaped triangular, widely spaced spiracles(1)
native to Eurasia & Africa, probably introduced into the New World during the colonial times(1)
larvae in decaying fibrous materials (straw bedding, wet hay/grass clippings, algal mats), cattle manure, soil mixed with manure and/or partially composted bedding, by-products of crop processing, etc.(1)
Adults of both sexes feed on blood during daytime; host specificity is low (mainly cattle and horses); the fully fed fly is sluggish and remains motionless near the host (Bishop 1913; Janovy & Roberts 2000)
Larvae feed on fecal materials and decaying organic matter, such as silage, rotting hay and grass clippings
eggs take 1-4 days to develop. The larval stage lasts 11-30+ days; third-instar maggots pupate for 6-20 days(2)
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