Synonyms and other taxonomic changes
Gomphocerus simplex S.H. Scudder, 1869, described from Delaware
Stenobothrus tricarinatus C. Thomas, 1873, described from Wyoming
Gomphocerus virgatus Scudder, 1875, described from Dallas, Dallas County, Texas
Gomphocerus navicula Scudder, 1876, described from southern Colorado
Eritettix variabilis Bruner, 1889, described from Silver City, Grant County, New Mexico
Eritettix vernalis Bruner, 1893, probably from Nebraska?
Eritettix simplex (Scudder) McNeill, 1897
Eritettix tricarinatus (Thomas) McNeill, 1897
Eritettix virgatus (Scudder) McNeill, 1897
Eupedetes carinatus S.H. Scudder, 1902, described from La Tremintina, San Miguel County, New Mexico
Eritettix brachypterus Bruner, 1904, described from northeast Durango, Mexico
Eritettix simplex ssp. tricarinatus (Thomas) Hebard, 1936
Eritettix simplex var. dorsalis Blatchley, 1920, based on a color form that lacks supplementary dorsal carinae on pronotum.
Length from vertex of head to tip of wings (or abdomen).
14-21 mm males
19-26 mm females
Very similar to Opeia obscura, differing most obviously in having margins of dorsal field of pronotum (in most individuals) bent inward toward each other near middle (nearly parallel occasionally in one color form). The margins are straight and parallel in O. obscura. Eritettix simplex is primarily adult in spring and O. obscura primarily adult in summer. In adult E. simplex the antennae are usually somewhat wider and darker toward the tip than toward the base (more so in north and east), and in O. obscura they are widest toward the base and usually not darker toward the tip. Some individuals of E. simplex have the sides of the top of the pronotum parallel, and can be very difficult to distinguish from O. obscura, especially in the Southwest, where differences in season and antennae may not hold up.
Eritettix abortivus is widespread in most of Texas east from the Pecos (except the Panhandle) and is in se. New Mexico and ne. Mexico. It differs in averaging smaller in size, having the head somewhat more rounded in shape, proportionately thicker hind femora, and in having shorter wings (shorter than abdomen in male and shorter than head + thorax in females). E. simplex only rarely has wings so short in males and (?) never in females. In E. abortivus adults generally mature earlier (often in late autumn) and both adults and nymphs overwinter.
E. obscurus is found in Florida, and has short wings.
Syrbula species are larger, with adults in summer, with longer narrower proportions (notably hind legs), and with more spines on hind tibiae (16 or more pairs).
Orphulella species have the margins of dorsal field of pronotum more gradually concave (as apposed to pinched near middle in Eritettix), and have dark triangle marks at only rear corners (front and back, and often connected - if present - in Eritettix). Male Orphulella have front and middle femora very thick (not so in Eritettix).
Widespread from Alberta to Arizona and east to Atlantic. Mostly missing from Atlantic and Gulf coastal plain, most of Texas, and rare and local in central lowlands of Mississippi River basin. Also in much of northern Mexico
Primarily open sunny short to mid grassland areas.
Overwinters as roughly 3rd to 5th instar nymphs. Adults mature in late winter or early spring and are mostly gone by summer. There is some evidence that there may be a later generation in some southern regions, which may be derived from spring hatching eggs, with nymphs and adults present in summer and some adults living into autumn. Eggs are laid in soil, mostly in spring.