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Family Heptageniidae - Flatheaded Mayflies

mayfly - Maccaffertium - male Epeorus pleuralis Mayfly Nymph - Maccaffertium Heptageniidae - Stenacron Mayfly larva - Epeorus Ephemeroptera - Mayflies - Stenonema femoratum Stenonema femoratum Mayfly - Leucrocuta
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Ephemeroptera (Mayflies)
Suborder Pisciforma
Superfamily Heptagenioidea
Family Heptageniidae (Flatheaded Mayflies)
126 spp. in 16 genera in our area(1), >600 spp. in 33 genera worldwide(2)
Base of m2 in FW nearly straight. Cubital intercalaries in FW in 2 parallel pairs. R4+5 in HW forked. Hind tarsi 5-segmented. Nymphs are flattened and streamlined. Adults are medium-sized to small, usually clear-winged.(3)
Keys to genera in(4)(5)(6)
worldwide & throughout NA(1)(2)
Nymphs on the underside of stones/logs in shallow, rapid streams or in lakes(7)
Works Cited
1.Mayfly Central
2.Barber-James H., Sartori M., Gattolliat J-L., Webb J. (2013) World checklist of freshwater Ephemeroptera species
3.A Field Guide to Insects
Richard E. White, Donald J. Borror, Roger Tory Peterson. 1998. Houghton Mifflin Co.
4.Aquatic Insects of North America
R. W. Merritt, K. W. Cummins, M.B. Berg. 2008. Kendall/Hunt.
5.Heptageniidae of the World. Part II: Key to the genera
J.M. Webb and W.P. McCafferty. 2008. Canadian Journal of Arthropod Identification, 7, 55 pp.
6.Freshwater macroinvertebrates of Northeastern North America
Peckarsky, B. L., P. Fraissinet, M. A. Penton, and D. J. Conklin, Jr. 1990. Cornell University Press, Ithaca, NY.
7.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.