Montana Field Guide

The following is taken from Hebard (1928), Brooks (1958), Helfer (1971), Otte (1981), Capinera and Sechrist (1982), Vickery and Kevan (1985), McDaniel (1987), Pfadt (2002), Capinera et al. (2004), Brust et al. (2008), and Scott (2010). This species is medium-sized, with large bulbous eyes. The median carina (ridge) of the pronotum (thorax) is distinct and cut with two sulci (grooves) resulting in high lobes or knobs (refer to close-up head and pronotum photo). The body color is brownish-gray and highly speckled with black. The forewings (tegmina) are long and extend well beyond the abdominal tip. The basal disk of the hindwings is yellow or reddish with a broad black band and transparent outer tip. The inner face of the hind femur is brownish and discolored, marked with black at the base. The hind tibia is mottled brownish-yellow.

Behavioral communication/crepitation*:
Solitary males of this species have not been observed to perform any crepitation flights, either for courtship or by disturbance. Flights are straight, but may make a midway right turn, covering a distance of 2 to 6 feet at a height of 4 to 10 inches above the ground. However, males do stridulate* during courtship, using both femora and producing soft, barely audible sounds. Femur-tipping is also used in courtship and during aggressive encounters with other males (Otte 1970).

*Crepitation is the sound produced by grasshoppers making a clicking or snapping noise with their wings when in flight, during courtship, territorial encounters or being disturbed.

*Stridulation is rubbing one body part against another, usually the hind femur against the forewing in the case of the Band-winged Grasshoppers. This is often used for attracting a female during courtship (Otte 1970).

This species overwinters in the egg stage. Nymphs hatch in late spring, adults occur from June to August, sometimes into early September (Vickery and Kevan 1985, Pfadt 2002, Capinera et al. 2004, Brust et al. 2008, and Scott 2010).

The following comes from Hebard (1928), Brooks (1958), Helfer (1971), Otte (1981), Capinera and Sechrist (1982), Vickery and Kevan (1985), McDaniel (1987), Pfadt (2002), Capinera et al. (2004), Brust et al. (2008), and Scott (2010). The body length to end of forewings for males is 18-24 mm, and females 22-30 mm.

Hayden’s Grasshopper is the only Derotmema species occurring in Montana, but visually it could be confused with the Kiowa Grasshopper (Trachyrhachys kiowa) and some species within the Trimerotropis genera.

Inhabits mixed-grass, shortgrass, and bunchgrass prairies, usually occupying disturbed sites with a high percentage of bare ground. Also frequently found in prairie dog towns, roadsides, abandoned fields and vacant city lots (Vickery and Kevan 1985, Pfadt 2002, and Scott 2010).

This species is a mixed feeder and consumes a variety of forbs, including dandelion, Knotweed (Polygonum aviculare), Russian thistle (Salsola tragus), Scarlet globemallow, Purslane, Scurfpea, Prairie clover, to name just a few. It also favors the leaves of such new-green grasses as Blue gramma (Bouteloua gracilis) and Western wheatgrass (Elymus smithii) (Vickery and Kevan 1985, and Pfadt 2002).

Little is known about Hayden’s Grasshopper’s reproductive cycle. From some observations, courtship is short and simple, consisting of the male femur tipping, stridulating, and mounting the female. No field observations occur relative to when eggs are laid, how many eggs they produce during their lifespan, or where they oviposit. Laboratory studies indicate they oviposit in bare soil, taking about one hour to complete oviposition. The pods are about an inch long, containing 16-17 pale yellow eggs, 4.3 mm long. There is one generation per year (Pfadt 2002).