Stizus occidentalis
This record describes Stizus occidentalis (species). Recorded family: Crabronidae. Recorded order: Hymenoptera.
Identification and Appearance
One of 4 western species and 2 extensively yellow species, S. occidentalis and S. iridis (range: UT, CA, AZ) share a largely yellow, red, and black coloration. S. occidentalis can be separated from S. iridis by its straighter margin of the clypeus and convex margins of T1 in dorsal view. The mesopleura, metapleura, and propodeum are also mostly black rather than yellow.
Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Hymenoptera (Ants, Bees, Wasps and Sawflies)
- Superfamily
- Trigonaloidea
- Family
- Crabronidae (Square-headed Wasps, Sand Wasps, and Allies)
- Subfamily
- Bembicinae
- Tribe
- Bembicini
- Genus
- Stizus
Imported taxonomy record. Source availability varies; see the source references and editorial policy below.
Habitat and Range
Geographic Range
AZ, CA, NV, UT
Additional species information
Species notes from the sources
Etymology: Stizus occidentalis J. Parker, 1929
About Flies: the wider group
Order-level background for Hymenoptera, the group containing Stizus occidentalis. 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 Stizus occidentalis (4)
Photo credits: Contributed by John S. Ascher; Additional contributions by Beatriz Moisset , PaleoJon , bdagley
Frequently Asked Questions About Stizus occidentalis
What is Stizus occidentalis?
Stizus occidentalis is a species in the family Crabronidae, within the order Hymenoptera.
How do you identify Stizus occidentalis?
One of 4 western species and 2 extensively yellow species, S. occidentalis and S. iridis (range: UT, CA, AZ) share a largely yellow, red, and black coloration. S. occidentalis can be separated from S. iridis by its straighter margin of the clypeus and convex margins of T1 in dorsal view. The mesopleura, metapleura, and propodeum are also mostly black rather than yellow.
Where is Stizus occidentalis found?
Range: AZ, CA, NV, UT