Arphia pseudonietana

Distinguished from the congeneric specklewinged grasshopper (Arphia conspersa) by seasonal timing—A. pseudonietana adults are present in late summer and fall, while A. conspersa adults appear in spring. The red-winged grasshopper has dark brown to black hind tibia with a yellow proximal annulus, whereas A. conspersa has pale yellowish-green hind tibia with fuscous annuli at both ends. A. pseudonietana also lacks the yellow abdomen characteristic of A. conspersa. Within its range, the combination of large size, dark body, and bright red hindwings in flight is diagnostic; however, yellow-winged morphs in the Great Lakes region require careful examination of tibial coloration and body pattern.

Occupies grass and grass-shrub habitats across western North America, reaching highest densities in mixedgrass prairie. In eastern and northern portions of its range, inhabits dry, sandy, or gravelly uplands and hilltops within tall and midgrass prairies. In western and southwestern range, occupies mesic grassland sites. At range periphery, restricted to specific habitat patches and less numerous.

Widely distributed in North America from Central America northward throughout the western United States and into Canada. Documented in the mixedgrass prairie of Wyoming, Nebraska, Colorado, South Dakota, North Dakota, and Montana; shortgrass prairie of Colorado; sand prairies of Colorado and North Dakota; bunchgrass prairie of Idaho; and montane areas to 10,000 feet in Colorado. Also recorded in Michigan, Wisconsin, and Minnesota (yellow-winged morphs).

Late-hatching species with eggs beginning to hatch in late May to mid-June depending on elevation and latitude. Nymphal development occurs June through August. Adults emerge mid-July in Idaho, late July in Wyoming, and persist until late October. Extended adult longevity of approximately 80 days exceeds that of many co-occurring species.

Feeds primarily on grasses and sedges, with documented consumption of at least 20 grass species and 4 sedge species. Primary host plants vary by habitat: blue grama, western wheatgrass, and needleleaf sedge in shortgrass prairie; western wheatgrass and buffalograss in mixedgrass prairie; needleandthread and western wheatgrass in sand prairie; Kentucky bluegrass and Penn sedge in northern sand prairie. Occasionally ingests small amounts of forbs including cudweed sagewort and scarlet globemallow. Nymphs feed on green leaves of downy brome, western wheatgrass, blue grama, sideoats grama, needleandthread, and green needlegrass. Adults show preference for junegrass and will feed heavily on young wheat leaves in laboratory conditions.

Eggs enter diapause at embryonic stage 19 (50% development) and overwinter, completing development the following spring. Hatching occurs over approximately two weeks. Nymphs pass through five instars over 42–56 days. Adults emerge mid-July to late July depending on location. Females begin oviposition at 4–5 weeks of age. Oviposition observed in September and October; females deposit 24–36 eggs in pods nearly 1 5/8 inches long, with froth occupying the upper portion. Eggs are tan to brown and 4.2–5.2 mm long.

Strong flier with sexually dimorphic flight characteristics. Males fly 10–30 feet when flushed, often with zigzagging, undulating flight accompanied by loud crepitation; when suddenly disturbed, flight becomes faster, silent, and smooth, ending with a sharp 180-degree turn before diving into vegetation. Females fly 5–60 feet, crepitate more softly and briefly, and alight without turning. Males perform conspicuous display flights on sunny days, rising vertically to approximately 4 feet with wings flashing red, then fluttering down slowly with loud crepitation—behavior functioning to aggregate sexes for courtship. Ground-dwelling; adults spend nights on bare ground patches or under grass canopy. Morning basking involves orienting side perpendicular to sun and lowering the hindleg to expose abdomen. During extreme heat, climbs vegetation and faces sun directly to shade the body.

Member of grassland orthopteran assemblages in mixedgrass and shortgrass prairie ecosystems. Functions as a generalist herbivore on perennial grasses and sedges. Low population densities (typically <1 adult per square yard) limit its functional impact relative to more abundant grasshopper species. Serves as prey for vertebrate and invertebrate predators in grassland food webs.

Minor pest in western grasslands. Feeds on valuable forage grasses and sedges but causes no serious losses due to consistently low population densities, which rarely exceed one young adult per square yard and are not known to reach outbreak densities. Contributes to overall grasshopper damage during general rangeland outbreaks. Adults invade winter wheat fields in fall, causing localized damage. Large size means individual consumption is substantial despite low numbers.

• Arphia conspersaCongeneric species with overlapping distribution; distinguished by spring adult presence versus late summer/fall for A. pseudonietana, pale yellowish-green hind tibia with dark annuli at both ends versus dark tibia with yellow proximal annulus, and yellow abdomen versus dark abdomen.

• BugGuide
• Wikipedia
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Grasshoppers of Colorado
• Specklewinged Grasshopper
• Redwinged Grasshopper
• Grasshoppers of Colorado
• Grasshoppers of Colorado
• Species Records and Accounts