Mantids are carnivorous insects distantly
related to grasshoppers and cockroaches. They are easily recognized
by their long, slender, neck-like thorax and grasping front legs but
not easily seen in their protective brown and green colourings. They
have prominent compound eyes, and threadlike antennae.
The elongated fore legs are adapted for grasping and holding prey.
Long, slender middle and hind legs are used for walking, standing
and leaping, giving this Okanagan species its common name, Agile
Ground Mantid.
The males are usually fully winged, but females are flightless
- their wings are greatly reduced, less than one-third the length
of the abdomen. As well, the males usually have a dark spot on their
hindwings and the females a roughened
pronotum.
The Ground Mantid can run with great agility and is often difficult
to capture. Flying males are often attracted to lights; all of the
11 males collected in Canada were collected at or near lights in
July and August.
This, the only native mantid in Canada, is restricted to the dry
shrub-steppes of the southern Okanagan Valley and is one of the
smaller mantids (25-30 mm in length). Despite recent entomological
attention to this habitat in the last decade, the ground mantid
has been found only a handful of times. Sometimes this mantid is
confused with the much larger Praying Mantid (Mantis religiosa),
which was brought to the Okanagan from Ontario (and originally from
Europe) to control grasshoppers.
Distribution
Map
Red dots indicate specimen records or confirmed breeding sites.
British Columbia
In Canada, the Ground Mantid is known only from the dry grasslands
of British Columbia in the extreme southern Okanagan Valley near
Oliver and Osoyoos.
North America
The Ground Mantid is widespread in the drier regions of North America
from Colorado and Arizona to Mexico, northwest to California, north
to Dakota, and occasionally to Texas. Although the species is not
yet recorded from Manitoba, Saskatchewan, or Alberta, it may be
expected to appear in the southernmost parts of these provinces.
Habitat
The Ground Mantid is a ground-dweller, but sometimes is found
on low vegetation. In shrubs and dry grasses such as sage and antelope
brush, this enigmatic dusty brown predator is hard to find.
Why is it endangered?
Rare invertebrates of the south Okanagan and Similkameen valleys
such as this species are threatened not by direct exploitation,
but by loss or degradation of their habitats. They are at risk because
their ecosystems are at risk.
The grasslands of the southern interior of the province are a
valuable agricultural resource, and their rich soils have been ploughed
and irrigated to produce tree fruits, grapes, and vegetables. Pesticide
use has probably had a great impact on native insects living in
around agricultural areas. As well, heavy grazing has altered the
plant composition of grasslands, changing the invertebrate communities.
The massive diversity of invertebrate species in British Columbia
makes it very difficult for entomologists to do a literature or
collection survey to determine which species are endangered or threatened.
Specialized, detailed surveys will be required for almost every
species that is suspected of being endangered. Despite a general
ignorance about invertebrate distribution, information is known
about a number of species that are confined to threatened habitats
of very limited extent in the Thompson-Okanagan valleys.
Biology
In the late summer and fall, female Ground Mantids lay a small,
rectangular egg mass about 7 mm long on the stems of low shrubs.
The eggs overwinter and hatch about six or seven month later. A
female may lay from three to six capsules of 50 to 400 eggs each.
The nymphs mature in about 13 weeks. Northern species have one brood
and hibernate in the egg stage.
Male Ground Mantids have been recorded living up to 47 days and
females up to 156 days.
Sources of more information
Related On-line Sites to Visit
Publications
Biodiversity of BC, Cannings, Ch.4 , 1994, p. 49-50
Rare inverts Brochure
Cannings, R.A. The Ground Mantis, Litaneutria minor (Dictuoptera:
Manitidae) in British Columbia. J. Entomol Soc. Brit Columbia.
84: 64-65.
Museum Specimens
Industry Canada