Ageneotettix deorum

(Scudder, 1876)

white-whiskered grasshopper, white whiskers grasshopper, sand grasshopper

Ageneotettix deorum is a -sized slant-faced widely distributed across North grasslands. It is frequently the in mixedgrass and bunchgrass prairie , reaching of 25 per square yard. The exhibits early-season hatching with nymphal development spanning 40–48 days. Adults are ground-dwelling, that feed on grasses and ground litter. show sensitivity to weather and , with outbreaks typically building over 3–5 years followed by sudden crashes.

Ageneotettix deorum side (48882159396) by Yellowstone National Park. Used under a Public domain license.

Ageneotettix deorum top (48882347822) by Yellowstone National Park. Used under a Public domain license.

Pronunciation

How to pronounce Ageneotettix deorum: /əˌdʒɛn.i.oʊˈtɛtɪks diˈɔːrəm/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

are -sized, reddish- with fuscous markings. The has a slightly slanted . are with the side light gray or whitish—this character provides the . are long, ranging from just short of to extending beyond the ; are speckled brown. Hind are red to orange with the end usually black. The inner of the hind tibia is diagnostic: elongated, 1.5 times as long as the other inner spur. Hind have black knees and three fuscous marks on the upper marginal area, with the middle mark triangular. show distinctive coloration: black along and side of head, side of , side of abdomen, and medial area of hind femur; light tan with few brown spots. 2–5 have a light tan below the and on the lobe.

Images

Habitat

Mixedgrass prairie, bunchgrass prairie, and tallgrass prairie. In tallgrass regions, highest occur on high ridges with grama or in grazed pastures of smooth brome or Kentucky bluegrass. Also inhabits shortgrass prairie, sand prairies, and disturbed areas including roadsides and borders. Altitudinal range extends to approximately 5,750 feet; absent above 7,500 feet.

Distribution

Widely distributed in grasslands of North America from southern Canada to northern Mexico, ranging east of the Rocky Mountains to the Atlantic Coast. Documented in Arizona, Colorado, Illinois, Indiana, Michigan, Montana, Nebraska, North Dakota, South Dakota, Wyoming, Kansas, Oklahoma, Texas, Iowa, and New Mexico.

Seasonality

Early-hatching . begin embryonic growth in summer, at 50% development (stage 19 embryo), and resume development in spring. Hatching occurs mid-spring, approximately simultaneous with Aulocara elliotti. Hatching period lasts 4–6 weeks. appear from mid-July in northern locations to earlier dates in southern portions of range. One annually.

Diet

Feeds primarily on grasses and sedges, including grama, western wheatgrass, needleandthread, Kentucky bluegrass, threadleaf sedge, and needleleaf sedge. Consumes grasses in proportion to their abundance. Also feeds extensively on ground litter including felled leaves, seeds, livestock , and dead . Laboratory tests indicate preference for wheat and Kentucky bluegrass over grasses. Forbs consumed only in small amounts.

Life Cycle

are deposited in shallow, horizontally-oriented pods just below ground surface, typically in grama or buffalograss sod. Pods contain 3–5 eggs (average 4), are 10–12 mm long, tough and curved with a slanted cap. Eggs are 5.0–5.3 mm long, pale to whitish. Embryonic development begins in summer, enters at stage 19, resumes in spring. develop through 5 (males occasionally 4, females occasionally 6) over 40–48 days. Females take longer than males to complete development. Preoviposition period approximately 14 days. Females successive clutches at approximately 3-day intervals.

Behavior

and ground-dwelling. At night, rests on bare ground or litter under grass . Morning basking occurs 1–2 hours after sunrise on the east side of grass crowns, body perpendicular to sun rays. Basking resumes 2–3 hours before sunset on west side of grass crowns. Normal daytime activities include pottering (intermittent wandering with frequent direction changes), feeding, mating, and . Activity slows when air temperatures reach 90°F or soil surface temperatures reach 120°F; individuals then seek of small shrubs. Evasive is straight, silent, low (3–6 inches), and short (3–6 feet). flights to high altitudes and urban areas documented, but no migrating swarms observed. Courtship involves males approaching moving females and using visual signals (raising and lowering hind and ). Copulation lasts approximately 5 minutes. Ovipositing females attract multiple attending males; after oviposition, female covers hole with litter and soil using hindlegs as brushes. Third and fourth show reduced feeding, increased antipredator behaviors, and reduced general activity in presence of lycosid ; fifth instars and show no significant behavioral response to spider predators.

Ecological Role

in mixedgrass prairie , frequently comprising 50% or more of . Contributes to overall forage damage in concert with other grass-feeding grasshoppers. for lycosid , birds, rodents, and ; subject to size-selective with vulnerability decreasing through nymphal development. preyed upon by birds, rodents, , and .

Human Relevance

Significant pest of rangeland grasses. occurs primarily through contribution to cumulative by grass-feeding . (25+ per square yard) can remove all green vegetation from pastures by early summer. Smaller body size (approximately half the weight of Aulocara elliotti) presumably reduces per- damage relative to larger . Subject to rangeland pest management programs including biological and chemical control.

Similar Taxa

Aulocara elliottiSimilar , distribution, and hatching time; distinguished by larger size (males ~580 mg vs. ~110 mg live weight), different pronotal structure, and lack of whitish .
Orphulella speciosaOverlaps in tallgrass prairie; distinguished by smaller size, strongly slanted , and different proportions.
Melanoplus angustipennisCo-occurs in sand prairie ; distinguished by -throated , diet including forbs, and different coloration.