I’ve always had a soft spot in my heart for unusual-looking orthopterans, like Tridactylidae and Tetrigidae, and for those (mostly) green songsters that entertain us in the summer months: Tettigoniidae. However, I’ve never really spent much time carefully observing short-horned grasshoppers, i.e., Acrididae. Writing for the North Carolina Insect of the Week series has given me an excuse to briefly yet regularly pull away from hymenopterans. Today I browsed the many drawers we have of mottled, brown grasshoppers, where I discovered this week’s beauty, Spharagemon cristatum (Orthoptera: Acrididae), described originally by Scudder in 1875 and commonly referred to as the ridgeback sand grasshopper.

Samuel Scudder described the species based on his observation of 19 specimens collected in Dallas and Waco, Texas. Since 1875 orthopterists have variably considered the species to be valid or to be a synonym of Spharagemon collare Scudder, 1872. The type specimen is deposited in the Academy of Natural Sciences in Philadelphia, alongside the type for S. collare.

Eric Eaton provides a nice diagnosis over at BugGuide. One can recognize this species based on its medium size (about 3 cm long), its mottled brown and gray appearance, the reddish hind tibia, and relatively long (about 1 cm) antennae – at least for a short-horned grasshopper. Look also for a median crest that runs longitudinally on the pronotum. Where it was collected can also contribute to a successful diagnosis, as one typically finds S. cristatum in lower latitudes, as opposed to its close relative, S. collare.

Like the vast majority of acridids, S. cristatum is an herbivore and feeds mainly on grasses and sedges. It is not considered to be a pest species, as they are typically found in low densities.

One can collect these effectively camouflaged insects in the coastal plain of North Carolina, especially in sandy habitats: open fields, along streams, in sand hills and scrub.

As of today, the specimens published in GBIF (Spharagemon cristatum in GBIF) lead one to believe this is mostly a Texan species, with perhaps one specimen collected in Florida. Our three specimens were collected east and south of Raleigh, which is a significant range expansion! Or it would be if GBIF was our only source of information on the range of this species. Eaton points out that NC might represent this grasshopper’s northern limits. They can be found at least as far west as New Mexico.

• Spharagemon cristatum Scudder, 1875 page at the Orthoptera Species File website.
• Spharagemon cristatum Scudder, S.H. 1875. Encyclopedia of Life, available from http://www.eol.org/pages/494521. Accessed 28 Oct 2010.