Numbers
5 subfamilies, 117 genera, and 620 species in North America (~240 spp. in
Melanoplus)
(1); ~8,000 species worldwide
(2)Identification
Medium to large orthoptera, familiar due to their diurnal habits, typically open habitat, and propensity to jump. Some species are quite colorful. Characteristics of Acrididae:
pronotum does not extend beyond base of wings
wings usually well-developed, but short (brachypterous) or absent (apterous) in some species, and wing length may be variable within a single species
antennae short, typically about one-half body length, with less than 30 segments
tympana (hearing organs), if present, are on the sides of the first abdominal segment
hind femora greatly enlarged (for jumping), typically about as long as hind wings
ovipositor short and stout
all tarsi have three segments (tarsal formula 3-3-3)
The six subfamilies used by
Orthoptera Species File Online are below, with some representative images. These have been arranged so that allied and/or similar-appearing subfamilies are adjacent, but there are many taxonomic issues in this group.
Acridinae - Silent Slantfaced Grasshoppers
Gomphocerinae - Slant-faced Grasshoppers
Cyrtacanthacridinae - Migratory Bird Locusts
Melanoplinae - Spur-throated Grasshoppers
Oedipodinae - Band-winged Grasshoppers
Habitat
Most species in grasslands, but some in forests, tundra, aquatic vegetation.
Season
Spring-fall in temperate areas, some species present all year in southern regions
Food
Typically eat foliage of forbs, grasses. Some species take a variety of plants, while others are restricted to a few species of closely related plants. They often take dry plant matter from the ground as well, and most will scavenge weak or dead grasshoppers when plant food is scarce.
Life Cycle
Some species have fairly elaborate courtship. Mating itself may take up to one hour, and male may ride on back of female for a period of a day or more, a behavior known as mate guarding. Females oviposit in loose soil (typically), among plant roots, in rotting wood, or even in dung. Clutches consist of 10-60 eggs, and females may lay up to 25 clutches over several weeks. Oviposition typically occurs in late summer, and the egg (as a developing embryo) overwinters. Eggs then hatch in spring. Life cycle is typically one year. A few species overwinter as juveniles (nymphs).
Remarks
The notorious migratory locust (
Schistocerca gregaria) of the Old World, recorded in literature since ancient times, is a member of this family. North American species of
Schistocerca do not form damaging swarms.
The extinct
Rocky Mountain locust,
Melanoplus spretus, was a swarming "locust" of western North America
(2).
