This key is intended a guide to the Orthoptera of the
Northern Great Plains. All of the species recorded (or likely to
be found) in the Dakotas are included. It is intended to work with adult specimens. For easier use, it is
divided into sections where (artificial) groups of species or genera are separated by short
roster of characters listed in bold-face type. Every
character will not fit for every species, but each species should be readily assignable to a group. These
smaller groups are then keyed out in pairs of opposing statements, each
successive level is indented-- see short example below. Since there are about 181 species of Orthoptera known from the
Dakotas, this procedure means that no key longer than about 20 couplets (like playing the game of twenty
questions) should have to be tackled.
A. Hind tibia red
a. Male with a pro-sternal hump.
a' Male without pro-sternal hump.
b. Hind femur gradually darkening to 'knee'; wings as long or longer than abdomen.
b.' Hind femur yellow with black cross-bands;
c. Male cercus 'thumb-shaped'; Wings usually less than 1/2 length of abdomen.
c.' Male cercus 'mitten-shaped'; Wings as long or longer than abdomen.
B. Hind tibia blue.
The major groups of Orthoptera
found in the Dakotas are as follows:
1. Caelifera are the Short-horned grasshoppers. Antennae are equal to or less than 1/2 length of the body, two very small species have the front legs modified for digging and the tarsi of the mesothoracic legs 2-segmented.
C1. Lubber grasshoppers
C4. Slantfaced hoppers
C6. Pygmy grasshoppers
C7. Pygmy mole crickets
2. Ensifera are the Long-horned grasshoppers. Antennae usually longer than body, if antennae are very short then the front legs are modified for digging and the tarsi of the mesothoracic legs are 3-segmented.
E1. Katydids & allies
E2. True crickets
E3. Mole crickets
E4. Sand crickets
E5. Camel crickets