These are members of the family Tettigoniidae. Most species are green with long wings and antennae. Five species in our area are short winged. The only other green ensifera are the tree crickets (Gryllidae: Oecanthinae). Tree crickets have three segmented mid-tarsi and a prognathus head. The Tettigoniidae can be divided into four groups for identification purposes:
1. Shield-backed crickets.
2. Large cone-headed grasshoppers.
3. Small cone-headed grasshoppers.
4. Katydids
Crickets are distinguished from all other orthopterans of the Dakotas in having three segmented tarsi. As with the katydids, males of true crickets stridulate by scrapping their tegmina together rather than the femur/tegmen system of the Caelifera.
The true crickets in our area can be divided into three groups:
1. Field and House crickets.
2. Tree crickerts.
3. Ground crickets and Bush crickets.
E3. Mole crickets (Gryllotalpidae)
Mole crickets take their common and Latin names from the resemblance both in foreleg shape and in habits to the mammalian moles (Talpidae). There are approximate 65 species World-wide divided unequally into the New World and largely Neotropical Scapteriscinae: 1 genus, 12 species, and the World-wide Gryllotalpinae: 5 genera, about 53 species. Mole crickets feed on plant roots and are occasional garden and greenhouse pests. Males sit at the entrance to their borrows and stridulate. A single species is known from the Dakotas, Neocurtilla hexadactyla.
E4. Sand crickets (Stenopelmatidae)
Members of this family are reedily separated from the crickets by their four segmented tarsi, and from the katydids in their anteriorly expanded pronotum, enlarged head and very short antennae– as well as wingless condition At least six genera and 30 species are known. This a relict group with members in southeast Asia, southern Africa, and Central America northward into the western United States. A single species occurs in our area, Stenopelmatus fuscus.
E5. Camel crickets (Rhaphidophoridae)
These are wingless crickets lacking a tympanum and with antennae longer than the body. World-wide, there are about 250 species in 30 genera. More than 130 species of Camel crickets occur in the United States, of these, 11 are known from the Dakotas.
A. Head with a small bifid conical projection.
Tachycines asynamorus
B. Tarsal formula 3-4-3.
Daihinia brevipes
C. Foretibia with a single dorso-lateral spine.
Udeopsylla robusta
D. Head with a small conical bulge, tarsal formula 4-4-4, foretibia without dorso-lateral spine.
Ceuthophilus, true camel crickets.
a. Dorsum with numerous raised nodules, base of male tibia with a flattened tooth. Male cercus abruptly swollen near base.
Ceuthophilus nodulosus
a.’ Dorsum without nodules, male tibia without tooth, Cercus evenly attenuate from base to apex.
b. Male with 8th tergite enlarged, covering 9th and expanded posteriad, subgental plate not divided by a median sulcus but may have a dorsal notch.
c. Ventral keel of tarsus with minute spines on at least basal half.
d. Male subgenital plate in posterior aspect about as long as wide. Widespread.
Ceuthophilus fusiformis
d.’ Male subgenital plate narrowly triangular and twice as long as wide. Eastern edge of the Dakotas only.
Ceuthophilus silvestris*
c.’ Ventral keel of tarsus smooth. Western plains.
Ceuthophilus alpinus
b.’ Male with 9th tergite emarginate, in ‘telescoped’ specimens often visible only as two lobes projecting beyond 8th tergite, or between cerci.
e. Male with hind tibiae bowed at base; general coloration dark with pale spots.
Ceuthophilus maculatus
e.’ Male with hind tibiae straight; general coloration transversely banded with light and dark, each tergite dark basad.
Centhophilus pallescens
b" Male with 9th tergite weakly acruate or convex, not emarginate nor lobate.
f. Dorsum finely piliose, specimens appearing dusty. Color pattern dark with light blotches.
Ceuthophilus pallidus
f.’ Dorsum glabrus and glossy. Specimens usually with a pale median stripe.
Ceuthophilus divergens.