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Photos of insects and people from the 2022 BugGuide gathering in New Mexico, July 20-24

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Species Tabanus atratus - Black Horse Fly

Black Horse Fly - Tabanus atratus Black Horse Fly - Tabanus atratus - female Black Horse Fly - Tabanus atratus - female Horse Fly - Tabanus atratus - female Horse Fly - Tabanus atratus - female Black Horse Fly (Tabanus atratus)? - Tabanus atratus - male large horsefly maybe, laying eggs. - Tabanus atratus - female Big-eyed Fly by Creek - Tabanus atratus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon (Orthorrhapha)
Infraorder Tabanomorpha
Family Tabanidae (Horse and Deer Flies)
Subfamily Tabaninae (Horse Flies)
Tribe Tabanini
Genus Tabanus
Species atratus (Black Horse Fly)
Explanation of Names
Tabanus atratus Fabricius 1775
atratus 'clothed in black'(1)
Adult 20-33 mm
Adult black, including wings, or nearly black, brown-purple
larva whitish, banded with black, up to 50 mm long(2)
se. Canada to FL-TX & n. Mexico(3); primarily eastern, although it has been collected throughout continental US (Long 2001)
Very wide range of habitats; generally near aquatic environments (Long 2001). Larvae live "along the margins of ponds and ditches"(4).
Apr-Dec in TX & FL (BG data)
Females feed on mammalian blood; males, which lack mandibles, feed on nectar and plant juices (Long 2001). Especially prone to attack cattle and other livestock(5) (2).
Life Cycle
Larvae require two years to complete life cycle(6)(2); adult males short-lived; females survive through fall(6). Eggs laid on vegetation overhanging permanent water(7)
Does not often bite humans but leaves painful memories when it does. Can transmit bacterial, viral, and other diseases such as surra and anthrax, to humans and other animals through its bite. Can be a serious problem for livestock. (Long 2001)
See Also
With known pathogenic transmission of Hog cholera virus, a disease that is only pathogenic to pigs and relatives; Anaplasma marginale, a bacteria that affects cattle; Trypanosoma evansi; and Trypanosoma theileri.
Internet References
Fact sheet (Long 2001)
Works Cited
1.Dictionary of Word Roots and Combining Forms
Donald J. Borror. 1960. Mayfield Publishing Company.
2.The Common Insects of North America
Lester A. Swan, Charles S. Papp. 1972. Harper & Row.
3.The horse and deer flies (Diptera: Tabanidae) of Texas
Goodwin and Drees. 1996. 1996. Southwestern Entomological Society.
4.Insects: Their Natural History And Diversity: With a Photographic Guide to Insects of Eastern North America
Stephen A. Marshall. 2006. Firefly Books Ltd.
6.National Audubon Society Field Guide to Insects and Spiders
Lorus and Margery Milne. 1980. Knopf.
7.National Wildlife Federation Field Guide to Insects and Spiders & Related Species of North America
Arthur V. Evans. 2007. Sterling.