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Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

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Species Cochliomyia macellaria - Secondary Screwworm

Blow fly - Cochliomyia macellaria - female Calliphorid or tachinid? - Cochliomyia macellaria Secondary screwworm? 2 - Cochliomyia macellaria - male Fly - Cochliomyia macellaria Cochliomyia macellaria? - Cochliomyia macellaria Common Green Bottle Fly? - Cochliomyia macellaria Blow Fly(?) Visiting a Fall Aster - Cochliomyia macellaria id fly to species? - Cochliomyia macellaria
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon (Calyptratae)
Superfamily Oestroidea
Family Calliphoridae (Blow Flies)
Subfamily Chrysomyinae
Genus Cochliomyia (Screwworm Flies)
Species macellaria (Secondary Screwworm)
Explanation of Names
Cochliomyia macellaria (Fabricius 1775)
Adults 5-8 mm, larvae (maggots) to 17 mm
New World (Canada to Chile & Argentina); transcontinental in NA(1)
carrion, decomposing tissues
Life Cycle
"The eggs are approximately 1 mm long and are laid in a loose mass consisting of 50 to 200 eggs. Group oviposition by several females results in large masses of thousands of eggs which may completely cover the decomposing carcass. The eggs hatch in about 24 hours (depending on air temperature) and the larvae feed on the carrion until they reach maturity. Larvae can reach the mature or postfeeding stage in as little as four days. Upon maturity, they migrate away from the carrion to search for a suitable pupation site. Pupation usually occurs within the first inch of topsoil or under leaf litter, rocks, or fallen limbs. During this time, the larval skin shrinks and hardens to form the puparium, which is dark brown in color. This stage may last from seven to ten days depending on temperature. The adults can live up to six weeks."(2)
will only infest an existing wound (thus the name "Secondary Screwworm")
Internet References
Fact sheet (Byrd 1998-2014)(2)