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Species Tritoxa flexa - Black Onion Fly

Unidentified Insect 43 - Tritoxa flexa Picture-winged Flies - Tritoxa flexa - male - female In the Onion Patch - Tritoxa flexa Ulidiidae, Tritoxa flexa, black onion fly - Tritoxa flexa Mating Black Onion Flies - Tritoxa flexa - male - female Mating Black Onion Flies - Tritoxa flexa - male - female Wasp / Fly hybrid - Tritoxa flexa Black Onion Fly - Tritoxa flexa
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon ("Acalyptratae")
Superfamily Tephritoidea
Family Ulidiidae (Picture-winged Flies)
Subfamily Otitinae
Tribe Cephaliini
Genus Tritoxa
Species flexa (Black Onion Fly)
circa 6-7 mm
Bold wing pattern and very dark--black.
Much of North America.
Life Cycle
Tritoxa flexa is known as the "Black Onion Fly" and is associated with cultivated garlic.
Print References
Marshall, color photograph--496.5 (1)
Lutz, illustrates T. flexa, 1st ed., plate LXXI, 3rd. ed., plate 54, size bar indicates length circa 8 mm. (2)
Swan and Papp, pg. 624, fig. 1339, illustrate T. flexa, give size as 0.25 inches, or 6.4 mm (3)
Internet References
North Carolina State Entomology Collection lists two species, both occurring in that state, with number pinned: T. flexa (21), T. incurva (64).
Preliminary Checklist of Minnesota Diptera lists T. flexa and T. incurva.
Works Cited
1.Insects: Their Natural History And Diversity: With a Photographic Guide to Insects of Eastern North America
Stephen A. Marshall. 2006. Firefly Books Ltd.
2.Field Book of Insects of the United States and Canada, Aiming to Answer Common Questions,
Frank Eugene Lutz. 1935. Putnam Pub Group.
3.The Common Insects of North America
Lester A. Swan, Charles S. Papp. 1972. Harper & Row.