West Virginia Snipe Flies

Family Rhagionidae

Snipe flies have a hemispherical head, somewhat long legs, and a conical abdomen. While not bristly, they are often partly covered with a light-colored pubescence The eyes of females are separated widely, but the eyes of males touch or nearly do. Spurs are present on the middle tibiae and sometimes the hind tibiae, but lacking on the front pair. The calypter is small or even vestigial.

The larvae feed on tiny invertebrates, and possibly plant material as well, developing in rotting wood or herbaceous plants, in mud, or in moss.

Snipe flies are closely related to Horse and Deer Flies, but fortunately for we easterners Snipe flies do not bite. (Some species in western North America do have a taste for human blood).

Family Micropezidae

Key traits for the Micropezid flies include long slender legs, and slender wings. In the Nearctic species the head is “more or less globular,” and in the subfamily Micropezinae the head is pointed forward. Vibrissae and ocellar bristles are lacking. The scutellum is small, and there is one pair of scutellar bristles (Steyskal, in McAlpine, 1987).

Many members of this family mimic wasps or ants. Larvae often develop in decaying leaves or other rotting plant material. The pupa is made from the final larval skin, and so the pupa resembles the last larval instar.

Oldroyd (1964) reported that Stilt-legged flies “prey on other insects, aphids and small flies, which they stalk through the vegetation.”

While more than 500 species have been described worldwide, in the Nearctic there are only 27 recorded species.