Striped Ground Cricket
Allonemobius fasciatus
Identification 5
The Nemobiinae Ground Crickets are represented by 7-10 species in Iowa in the genera Allonemobius, Eunemobius, and Neonemobius. They are all small crickets, usually 15 mm or less and can be frustrating to try to identify. Some are best identified by song. A. fasciatus appears to be encountered by naturalists most often. Allonemobius (5 species in Iowa) can be recognized by their straight ovipositor that is longer than other genera (nearly as long or longer than hind femur). They are also larger, if you care to measure the length. Supposedly, A. fasciatus can be recognized by the pattern of stripes on top of the head. However, comparing diagrams in Bland (2003), Vickery and Kevan (1985), and the key from North Dakota, shows that it is sometimes not quite so simple. In general, A. fasciatus has more distinct stripes, but in some individuals the stripes are indistinct. The shape of the pronotum can be just as helpful in identification. A. fasciatus has a barrel-shaped pronotum from above, which is the same width at the front end (anteriorly) and rear of pronotum (posteriorly). In A. allardi the pronotum narrows subtly toward the front. This gives A. allardi's head a slightly retracted appearance. A. fasciatus is usually dark brown, but light brown individuals occur and can be confused with A. tinnulus or Neonemobius variegatus. Body length in A. fasciatus is 7-11 mm. In micropterous/brachypterous individuals, wings cover about half the abdomen in females and about 3/4 the abdomen in males. Most Nemobiinae have short-winged (micropterous or brachypterous) and long-winged individuals (macropterous). Long-winged individuals are commonly attracted to lights at night.
Other Allonemobius species are less likely to be confused with A. fasciatus. A. maculatus is the most easily identified Allonemobius because of spotting and head pattern. A. griseus occurs only in northwest Iowa and usually has a gray appearance. A. tinnulus has a reddish brown unmarked head. A. socius is morphologically indistinguishable from A. fasciatus and must be identified by song, but currently this species is unknown from Iowa, though it is known from northern Missouri.
Resources 5
Key to Allonemobius in the Dakotas: https://www.ndsu.edu/ndmoths/hopper/fasciatuscomplex.htm
Bland, R.G. 2003. The Orthoptera of Michigan – Biology, Keys, and Descriptions of Grasshoppers, Katydids, and Crickets. Michigan State University Extension, Extension Bulletin E-2815. https://archive.lib.msu.edu/DMC/Ag.%20Ext.%202007-Chelsie/PDF/e2815.pdf
Vickery, V.R. and Kevan, D.K., 1985. The grasshoppers, crickets, and related insects of Canada and adjacent regions. Ulonata: Dermaptera, Cheleutoptera, Notoptera, Dictuoptera, Grylloptera, and Orthoptera. Insects and Arachnids of Canada, Part 14. Agriculture Canada. https://publications.gc.ca/collections/collection_2016/aac-aafc/agrhist/A42-42-1985-14-eng.pdf
SINA: https://sina.orthsoc.org/543a.htm
Occurrence 5
Statewide.
Habitat 5
Common in many mesic habitats, including gardens and yards. A. allardi and A. maculatus tend to occur in drier microhabitats.
Fontes e Créditos
- (c) Tim Hite, alguns direitos reservados (CC BY), uploaded by Tim Hite
- (c) John Beetham, alguns direitos reservados (CC BY-NC-SA), https://www.flickr.com/photos/dendroica/9858155435/
- (c) Matt Pelikan, alguns direitos reservados (CC BY), uploaded by Matt Pelikan
- (c) Jean-François Roch, alguns direitos reservados (CC BY-NC), uploaded by Jean-François Roch
- (c) Tyler Grant, alguns direitos reservados (CC BY-SA)
