|scientific name Stenopogon |
Very diverse; in Alberta, mostly prairie, grassland, dry forests and gravelly river banks.
Adults are most visible in the summer months, often seen mating or feeding
Stenopogon are robber flies (Asilidae), stout or robust, with elongate and tapered abdomens. Viewed from the front they have a circular head and have numerous strong bristles. The only firm character separating them from members of the genus Scleropogon Loew is that the metapleuron of the former is micropubescent (appears bare to the naked eye) only.
Stenopogon are members of the tribe Stenopogonini, whose front tibiae lack apical spines. The wings are also elongate, with a brown or yellow tinge and the first posterior cell is often widely open. Exceptions do occur. The abdomen is broad at base, but is never wider than the mesosternum. The genital cavity is often open, and males have an elongated 8th abdominal tergite. The long cylindrical proboscis is directed downward.
Asilidae eggs are deposited by females in low growing shrubs and grasses or other similarly hidden places. Most species lay eggs in large numbers within a protective coating. Larvae are predacious, like the adults. Asilidae over-winter as larvae and pupate in the soil. Puparia migrate to the surface and emerge as adults. Complete development can take up to three years and is dependant on climate conditions. (Finn, 2003)
This is a common genus which covers a broad area, and the known species are equally divided between the two hemispheres. Climate change and human land disturbance are expected to effect distributions, but populations have not yet appeared to decline (Cannings, 1989).
Stenopogon have been known to feed on other Asilidae, bees, wasps, dragonflies and other insects or various sizes. Some will also prey on spiders.
There are a possible 5 species in Alberta, but Stenopogon are literally found all over the world. However, it is suggested that some Australian species are misplaced within this group and further research may reveal otherwise (Hull, 1962).
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