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Species Cephus cinctus - Western Wheat Stem Sawfly

Representative Images

Ichneumonidae? - Cephus cinctus - female Ichneumonidae? - Cephus cinctus - female ID this colorado bug - Cephus cinctus Ichneumon Wasp? - Cephus cinctus - female Ichneumon Wasp? - Cephus cinctus - female id help - Cephus cinctus Stem Sawfly - Cephus cinctus Stem Sawfly - Cephus cinctus

Classification

Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon ("Symphyta" - Sawflies, Horntails, and Wood Wasps)
Family Cephidae (Stem Sawflies)
Tribe Cephini
Genus Cephus
Species cinctus (Western Wheat Stem Sawfly)

Other Common Names

American Wheat Stem Sawfly (a misnomer, given evidence of origin in northeastern Asia(1))
Wheat Stem Sawfly (also applied to C. pygmaeus in Europe)

Synonyms and other taxonomic changes

Cephus graenicheri Ashmead, 1898
Cephus occidentalis Riley & Marlatt, 1891

Explanation of Names

Cephus cinctus Norton 1872
cinctus = 'belted, banded'

Size

up to 10 mm(1)

Range

NA (probably introduced, now transcontinental: PA-GA to BC-CA), ne. Asia (Altai to Kamtschatka & n. Japan)(1)

Food

hosts: grain crops (esp. wheat), feral & native grasses (members of several Holarctic grass genera); in dry years, C. cinctus would literally starve on the truly native hosts(1)

Life Cycle

Larva overwinters within a wheat stub, under the ground. In the spring it pupates and emerges as an adult in June. The female lays a single egg and the larva feeds inside the stem until late summer.
females show little selectivity and would lay eggs into any available stem of the correct size, including those of plants where larvae will not mature(1)
details in(2)

Remarks

earliest NA record: CO, NV 1872; major pest of wheat and other cereals since 1895 (economically important damage is concentrated in the n. Great Plains)(1)

Works Cited

1.On the geographic origin of the wheat stem sawfly (Hym.: Cephidae): a new hypothesis of introduction from northeastern Asia
Ivie M.A. 2001. American Entomologist 47: 84-97.
2.Wheat stem sawfly biology
Fulbright J., Wanner K., Weaver D. 2011. Montguide MT201107AG, 3 pp.
Contributed by Beatriz Moisset on 17 July, 2009 - 6:51pm
Additional contributions by Chuck Entz, v belov, PaleoJon
Last updated 25 May, 2024 - 11:32pm

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