Hesperotettix viridis

Distinguished from the similar Hypochlora alba (cudweed grasshopper) by: medium green vs. pale green coloration; black antennae with pale anterior annuli vs. green antennae; hind femur medium green with black spots/chevrons vs. pale green with brown spots. Distinguished from other Hesperotettix species by host plant association and male genitalia structure. Nymphs identifiable by green body with fuscous spots, cream median carina on pronotum, and color pattern of antennae and hind legs.

Grasslands, sagebrush shrub associations, and abandoned fields where host plants occur. Distribution is patchy and closely tied to presence of specific host plants, particularly snakeweeds (Gutierrezia), goldenrods (Solidago), and rabbitbrushes. In the West, often found in mixedgrass prairie and sagebrush steppe; in the East, less common and more restricted to suitable host plant patches. Elevation range from lowlands to at least 7,600 feet resident populations, with individuals occasionally found up to 11,500 feet.

North America; widespread in western United States and Canada, patchier in eastern portions. Documented in 11 U.S. states and 3 Canadian provinces. Specific records from Wyoming, Colorado, New Mexico, Kansas, Nebraska, North Dakota, South Dakota, Montana, Arkansas, Illinois, Indiana, and northeastern Mexico. Distribution limited by host plant availability, creating discontinuous populations.

Eggs hatch in intermediate period, two to three weeks after early-hatching species like Ageneotettix deorum. Hatching mid-June in northern mixedgrass prairie (Wyoming), six weeks earlier in New Mexico. Nymphal development approximately 55 days (44-46 days in some Colorado populations). Adults present from late July through early October. One generation annually; eggs overwinter in soil in embryonic diapause (stage 19).

Oligophagous feeder specializing on Asteraceae forbs, particularly snakeweeds (Gutierrezia sarothrae, G. microcephala), threadleaf snakeweed, goldenrods (Solidago mollis), rabbitbrushes (Ericameria, Chrysothamnus), and other composites. Documented to feed on at least 34 forb species across its range. Prefers snakeweeds to rabbitbrush and burroweed based on food preference tests. Consumes leaves, stem cortex, and flower buds. Feeds in short bouts of less than three minutes, primarily during daylight hours. Also ingests trace amounts of grasses, flower petals, pollen, fungi, and arthropods.

• Gutierrezia sarothrae - primary hostbroom snakeweed
• Gutierrezia microcephala - primary hostthreadleaf snakeweed; study populations in New Mexico fed almost exclusively on this species
• Solidago mollis - primary hostvelvet goldenrod; host-associated genetic lineage documented
• Ericameria nauseosus - secondary hostrabbitbrush
• Chrysothamnus viscidiflorus - secondary hostrabbitbrush
• Artemisia ludoviciana - secondary hostwestern ragweed, eaten in lesser amounts

Incomplete metamorphosis (hemimetabolous). Eggs laid in soil at approximately 1 inch depth, enclosed in tough-walled pod 5/8 to 3/4 inch long containing 8-12 tan eggs (4.3-4.9 mm long). Eggs enter diapause at embryonic stage 19 and overwinter. Hatching begins mid-June in northern populations, earlier in southern locations. Five nymphal instars required to reach adulthood; nymphal period averages 55 days in field (longer than ground-dwelling grasshoppers due to cooler temperatures in elevated perches). Adults emerge in late July to August and persist until October. One generation per year.

Phytophilous species spending most of active life on host plants. Roosts head-up on stems during night. After sunrise, basks by turning side perpendicular to sun rays while maintaining vertical position on plant; later basks horizontally on ground surface with hindleg lowered. Feeds in short bouts, continuously sampling different plants; tenure on individual plants typically less than one day. Abandons plants more quickly when growing in dense stands and when plants have prior feeding damage; remains longer on protected, high-quality plants. When disturbed, jumps 2-8 inches between stems or up to 2 feet to ground, then immediately returns to host plant. Does not drop to ground to evade predators. At high temperatures (>100°F), moves to shady side of plant stem. Mating observed in early morning (6:46-9:25 a.m.); oviposition at base of host plant in bare ground or shortgrass clumps, with female holding upright plant and working ovipositor into soil over 75+ minutes.

Specialist herbivore that can significantly impact host plant populations. Feeding reduces shoot water content, nitrogen content, and edible biomass of host plants over the growing season. In New Mexico, high densities cause substantial mortality of snakeweed seedlings and one-year-old plants; older plants tolerate damage better but may die prematurely with heavy defoliation. Acts as natural biological control agent of snakeweeds, which are competitive, low-forage-value plants that can poison livestock. Equalizes cumulative feeding damage across host plant population through selective foraging on less-damaged plants. Provides food source for insectivores; specific predators not documented in sources.

Investigated as biological control agent for invasive snakeweeds (Gutierrezia spp.), which reduce forage quality, compete with desirable plants for soil moisture, and can cause livestock abortion when ingested. Studies in New Mexico demonstrated feasibility of using this grasshopper to suppress broom snakeweed populations. Not considered an agricultural pest; feeds on plants with little or no forage value. No significant negative economic impacts reported.

• Hypochlora albaBoth are green, spur-throated grasshoppers found in similar habitats. H. viridis is medium green with black antennae (pale annuli), H. alba is pale green with green antennae. H. viridis has hind femur medium green with black spots/chevrons; H. alba has hind femur pale green with brown spots. H. alba is monophagous on Artemisia ludoviciana; H. viridis is oligophagous on multiple Asteraceae.
• Hesperotettix speciosusCongeneric spur-throated grasshopper with similar morphology. Distinguished by different host plant associations and male genitalia structure.
• Melanoplus speciesOther spur-throated grasshoppers in same subfamily. Distinguished by color pattern, wing length, and host plant specificity; most Melanoplus are more polyphagous.

• grasshopper
• Acrididae
• Melanoplinae
• specialist herbivore
• host-associated differentiation
• biological control
• Asteraceae
• snakeweed
• North America
• oligophagy
• phytophilous
• spur-throated
• ecological speciation

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Snakeweed Grasshopper
• Grasshoppers of Colorado
• Grasshoppers of Colorado
• Cudweed Grasshopper
• Species Records and Accounts
• Grasshoppers of Colorado
• Local Food Depletion and the Foraging Behavior of a Specialist Grasshopper, Hesperotettix Viridis
• Comparative genome scan detects host‐related divergent selection in the grasshopper Hesperotettix viridis
• Host plant‐associated genetic differentiation in the snakeweed grasshopper, Hesperotettix viridis (Orthoptera: Acrididae)
• Performance Tradeoffs for Two Hosts within and between Populations of the Oligophagous Grasshopper Hesperotettix viridis (Acrididae)
• Divergent host plant adaptation drives the evolution of sexual isolation in the grasshopper Hesperotettix viridis (Orthoptera: Acrididae) in the absence of reinforcement