Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

Calendar
Upcoming Events

Photos of insects and people from the 2024 BugGuide gathering in Idaho July 24-27

Moth submissions from National Moth Week 2024

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

Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

Photos of insects and people from the 2019 gathering in Louisiana, July 25-27

Photos of insects and people from the 2018 gathering in Virginia, July 27-29


Previous events


TaxonomyBrowse
Info
ImagesLinksBooksData

Species Cephus cinctus - Western Wheat Stem Sawfly

Ichneumonidae? - Cephus cinctus - female Ichneumonidae - Cephus cinctus Stem Sawfly - Cephus cinctus - female stem sawfly - Cephus cinctus Stem Sawfly - Cephus cinctus Stem Sawfly - Cephus cinctus Stem Sawfly - Cephus cinctus Cephus from montane Sierra Nevada - Cephus cinctus - male
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.