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Family Tetrigidae - Pygmy Grasshoppers
Classification Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Class Insecta (Insects)
Order Orthoptera (Grasshoppers, Crickets, Katydids)
Suborder Caelifera (Grasshoppers)
Family Tetrigidae (Pygmy Grasshoppers)
Other Common Names Grass Locusts, Pygmy Locusts, Grouse Locusts
Explanation of Names Author of family is Serville, 1838 ( OSF).
Family name is from genus Tetrix (Latreille, 1802). A related zoological name is that of the bird Tetrao tetrix (Linneaus, 1758), the Black Grouse. Tetrao, grouse, is from a Greek word, τεραων, meaning pheasant or grouse (1). This relationship is seen in the common name grouse locusts for the Tetrigidae, but the exact connection between the locust and the grouse is not clear.
It seems likely that tetrix, in the case of both the grouse and the orthopteran, is from Latin tetricus, taetricus, meaning harsh, sour, severe (1), (Latin dictionary). The extended meaning of the English word derived from it, tetric, is rugged, which would certainly apply to the rugged sculpturing of many species in the Tetrigidae. Perhaps this is the meaning of the species name for the Black Grouse, Tetrao tetrix, and it was picked to accompany the (unrelated?) genus name for alliterative reasons. (The male Black Grouse is certainly bold, and perhaps rugged.) Then, perhaps ( !) Tetrix (orthopteran) was derived from the name of that particular grouse. Certainly the common name grouse locusts is a reference to Tetrao tetrix the grouse. This one is a real puzzle.
Numbers Arnett lists six genera, 29 North American species (2). Worldwide, about 27 genera and 1400 species ( Wikipedia) (3).
Two subfamilies, Tetriginae and Batrachideinae (2), the latter sometimes listed as a separate family ( Wikipedia).
Size 6-16 mm (body length)
Identification Tiny orthoptera, similar in form to Acrididae, usually associated with wet areas. Characteristics:
less than 20 mm length, often smaller
pronotum is highly elongated, tapered, usually covers abdomen
tegmina (forewings) small, padlike, sometimes absent, may be exposed or covered by pronotum
front and middle tarsi with 2 segments, hind tarsi with 3 segments (formula 2-2-3)
hind tibiae expanded (for swimming!) in some species
a single species can have short-winged and long-winged forms, or lack wings altogether--these forms may appear quite different
auditory and stridulatory organs absent
Coloration and pattern, even within a single species, are variable. Often strongly sexually dimorphic, both in size (females usually larger) and in coloration. Some specimens appear green due to growth of algae. Helfer (4) is the only reference in popular literature (though out-of-print) that has keys to this family.
Habitat Usually near water, such as ponds and streams. Occasionally found in dry habitats, woodlands, old fields, sandy areas with lichen.
Season Spring, fall. May-June, September (Minnesota). Much of year in southern United States, apparently.
Food Eat roots of plants or seedlings, mosses, fungi, algae, organic muck.
Life Cycle Typically overwinter as adults and breed in late spring. Some species form breeding aggregations on the margin of ponds. One brood per year in north, two in southern areas. Adults may live two years or more. Reported to sometimes reproduce by parthenogenesis (4).
Semi-aquatic--eggs sometimes laid underwater. Some adults are reported to jump into water and swim away (underwater) as an escape mechanism.
See Also Acrididae - Short-horned Grasshoppers
Print References The Century Dictionary--entries for tetric and Tetrao--there are no entries for Tetrix or Tetrigidae, unfortunately (1)
Bland, p. 125--family description, illustrates 8 species (3)
Helfer, pp. 82-94, has keys, illustrations, for 16 or more species (4)
Castner, p. 64, gives family characteristics (5)
Capinera, pp. 150-151, plate 33, describes and illustrates two species (6)
Internet References Orthoptera of the Northern Great Plains: list, gives common names. Key--gives a key to some genera and species of Tetrigidae, and other members of the suborder Caelifera.
Subfamily Tetriginae: Nomotettix cristatus; Tetrix ornata, T. arenosa angusta; Neotettix femoratus, N. proavus; Paratettix cucullatus; Subfamily Batrachideinae: Tettigidea lateralis lateralis, T. armata.
Orthoptera of Alabama--species descriptions
Works Cited | 7. | How to Know the Insects By Roger G. Bland, H.E. Jaques |  |
Contributed by Troy Bartlett on 16 February, 2004 - 12:32pm Additional contributions by cotinisLast updated 25 April, 2007 - 9:38am |
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