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Genus Isodontia - Grass-carrying Wasps

Small Thread-waist? - Isodontia mexicana fly or wasp - Isodontia mexicana Isodontia? - Isodontia mexicana Brown-legged Grass-carrier - Isodontia auripes - male Isodontia auripes Sphecidae, Grass Carrying Wasp, dorsal - Isodontia mexicana Isodontia - Isodontia mexicana Isodontia - Isodontia mexicana
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon (Aculeata - Ants, Bees and Stinging Wasps)
No Taxon (Apoid Wasps (traditional Sphecidae))
Family Sphecidae (Thread-waisted Wasps)
Subfamily Sphecinae
Tribe Sphecini
Genus Isodontia (Grass-carrying Wasps)
Synonyms and other taxonomic changes
Isodontia Patton 1880
Numbers
6 spp. in 2 subgenera in our area(1), >60 spp. worldwide(2)
Identification
Medium-sized dark sphecids, often seen carrying grass to nests.
Hairs on thorax golden
I. elegans - petiole black, legs red, abdomen often red-marked (variable from entirely red to almost entirely black), wings light and often with orange tint

I. exornata - petiole red, legs red, abdomen black, wings dark with some blue reflections

Hairs on thorax pale
I. apicalis - body entirely black, head of female blocky behind eyes, wings always dark and typically with blue reflections

I. mexicana - body black with occasional brown spot on T1, head of female short behind eyes, wings hyaline to dark with blue reflections

Hairs on thorax black
I. apuripes - body black, legs brownish-red, wings dark with strong blue reflections

I. philadelphica - body entirely black, wings dark with strong blue reflections
Range
worldwide(2)
Habitat
Open areas, fields, grass
Season
in NC: I. auripes Jun-Oct, I. azteca May-Oct(3); Jul-Aug in MI(4)
Food
Adults take nectar. Larvae are fed Gryllidae (particularly tree crickets) or other Orthoptera.(5)
Life Cycle
Females make nests in a tree, hollow stem or other cavity, divide into sections and close with grass. They provision with Orthoptera (Tettigoniidae, Gryllidae). Can be two generations per year (I. mexicana in PA)
1. Larva 2. Cocoon and food remnants in hollow stem 3. Adult female 4. Adult male. 5. Parasitic fly's puparia.

grass-carrying habits, nest(6); nesting behavior of I. harrisi(7)
Adults emerge in early summer. Female collects blades of grass and grass and hay stems to line the nest cavity. The nest is stocked with tree crickets (Oecanthus spp.) The larvae reach the appropriate size in 4–6 days at 70–75°F and pupate. The adults emerge in 2–3 weeks. In Pennsylvania, I. mexicana typically produce two generations a year. (Jacobs 2014)
Remarks
These wasps commonly make their nest in the narrow track found above outer windows.
Works Cited
1.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.
2.Catalog of Sphecidae sensu lato
3.Insects of North Carolina
C.S. Brimley. 1938. North Carolina Department of Agriculture.
4.The Sphecid Wasps of Michigan (Hymenoptera: Sphecidae: Sphecinae), by M.F. O'Brien
5.Solitary Wasps: Behavior and Natural History (Cornell Series in Arthropod Biology)
Kevin M. O'Neill. 2000. Comstock Publishing.
6.The Wasps
Howard Ensign Evans, Mary Jane West Eberhard. 1970. University of Michigan Press.
7.Wasp Farm
Howard Ensign Evans. 1963. Comstock Publishing.