Velvet-striped Grasshopper
Eritettix simplex
Identification 6
Adults appear in the spring and are most common in April and May. Overwinters as nymphs. Green to brown. The top of the head has 3 lengthwise carinae (raised ridges or seams), one along the mid-line and one on each side (lateral carinae). These continue back along the top of the pronotum, where the lateral carinae are cream colored. The lateral carinae and the pronotum are usually noticeably pinched toward the middle, but not always. Froeschner (1954) recognized two subspecies, E. s. simplex in the eastern half of Iowa that has straight lateral carinae and E. s. tricarinatus in the western half of Iowa that has pinched lateral carinae. They intergrade in central Iowa. If the lateral carinae are straight or nearly so, this species can be more difficult to distinguish from other species. It usually has dark stripes extending backward on the head and pronotum inside the lateral carinae and a central lighter dorsal stripe.
Similar to Pasture Locust and Obscure Grasshopper (though Obscure Grasshopper has not recently been recorded in Iowa). Pasture Locust appears as adults in the fall. The Pasture Locust pronotum is concave on the sides from above, rather than pinched, and has dark triangle marks at rear corners of the pronotum. Obscure Grasshopper also overwinters as nymphs, but adults appear in the summer, rather than spring, according to BugGuide. Obscure Grasshopper always has parallel margins on the pronotum (not pinched or concave), the top of the head has a single carina, and the antenna are ensiform (flattened). However, Eritettix simplex nymphs have rather ensiform antennae. Another species that could be confused with Eritettix simplex is Amphitornus coloradus, though it may be less likely to occur than even Obscure Grasshopper. Among other things, A. coloradus has blue tibiae.
Resources 6
Grasshoppers of the Western U.S.: https://idtools.org/id/grasshoppers/factsheet.php?name=13175
Capinera, J.L., R.D. Scott, and T.J. Walker. 2004. Field Guide to Grasshoppers, Katydids, and Crickets of the United States. Cornell University Press.
Otte, D., 1981. The North American Grasshoppers, Vol. I. Acrididae: Gomphocerinae and Acridinae. Harvard University Press.
Occurrence 6
Statewide.
Habitat 6
Grassland, often with Blue Grama, a preferred food plant. Relict prairies, grassy openings in woodlands.
Fontes e Créditos
- (c) adriscoll, alguns direitos reservados (CC BY-NC), uploaded by adriscoll
- (c) Steven Mlodinow, alguns direitos reservados (CC BY-NC), uploaded by Steven Mlodinow
- (c) Zoology123, alguns direitos reservados (CC BY-NC), uploaded by Zoology123
- (c) leptim, alguns direitos reservados (CC BY-NC)
- (c) Alex Harman, alguns direitos reservados (CC BY-NC), uploaded by Alex Harman
- (c) Tyler Grant, alguns direitos reservados (CC BY-SA)
