Western Wheat Stem Sawfly
Cephus cinctus
This record describes Cephus cinctus (species). Recorded family: Cephidae. Recorded order: Hymenoptera.
Identification and Appearance
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)
Wikipedia reference for Cephus cinctus: http://en.wikipedia.org/wiki/Cephus_cinctus.
Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Hymenoptera (Ants, Bees, Wasps and Sawflies)
- Family
- Cephidae (Stem Sawflies)
- Tribe
- Cephini
- Genus
- Cephus
Imported taxonomy record. Source availability varies; see the source references and editorial policy below.
Habitat and Range
Geographic Range
NA (probably introduced, now transcontinental: PA-GA to BC-CA), ne. Asia (Altai to Kamtschatka & n. Japan)
Diet and Behavior
Diet: 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
Life History
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.
Additional species information
Species notes from the sources
Etymology: Cephus cinctus Norton 1872
About Flies: the wider group
Order-level background for Hymenoptera, the group containing Cephus cinctus. Species-specific details appear above.
Group overview
Hymenoptera includes over 150,000 described species of ants, bees, wasps, and sawflies. Earth harbors approximately 20 quadrillion (20×10^15) ants, with a combined biomass of ~12 megatons of dry carbon - exceeding the combined biomass of all wild birds and mammals (PNAS, 2022).
Ecological role of the group
About 35% of the world's food crops depend on animal pollinators. The chocolate industry, valued at over $100 billion, depends on pollinating flies and midges. Ants are the dominant soil engineers in most terrestrial ecosystems, turning more soil than earthworms in many habitats.
Economic and practical significance of the group
Pollinators contribute $235-577 billion worth of annual global food production (FAO). In the U.S., bee pollination alone benefits crops valued at $18 billion annually, and honey bees are responsible for $5.4 billion in agricultural productivity. Between April 2023-2024, 55.1% of managed honey bee colonies were lost. The U.S. bee population dropped from 5 million to 2.5 million.
Recorded sources for this group: FAO, USDA, EPA, PNAS (2022), US Fish & Wildlife Service. Imported estimates may describe particular regions or reporting periods.
Photos of Western Wheat Stem Sawfly (3)
Photo credits: Contributed by Beatriz Moisset; Additional contributions by Chuck Entz , v belov , PaleoJon
Frequently Asked Questions About Western Wheat Stem Sawfly
What is Western Wheat Stem Sawfly?
Western Wheat Stem Sawfly (Cephus cinctus) is a species in the family Cephidae, within the order Hymenoptera.
How big is Western Wheat Stem Sawfly?
up to 10 mm
Where is Western Wheat Stem Sawfly found?
Range: NA (probably introduced, now transcontinental: PA-GA to BC-CA), ne. Asia (Altai to Kamtschatka & n. Japan)
What does Western Wheat Stem Sawfly eat?
The diet of the Western Wheat Stem Sawfly includes 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.
What is the life cycle of a Western Wheat Stem Sawfly?
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.