tachinid flies

Exoristinae is a very large subfamily of the very large family of tachinid flies. About half of all described Tachinidae species belong in the family Exoristinae. There are more than 3,687 described Exoristinae species in 246 genera in 11 tribes worldwide, more than 580 species in about 130 genera in 8 tribes in North America north of Mexico, and at least 38 species in 23 genera in 5 tribes in Minnesota.

The larvae of Exoristinae are parasitoids of eight orders of insects. They never parasitize true bugs (Heteroptera). Most species parasitize the larvae of butterflies and moths (Lepidoptera). Females deposit an egg on or in the vicinity of a host larva, rarely directly into the host body. Some species parasitize adult beetles (Coleoptera), stick insects (Phasmida), and cockroaches and termites (Blattaria). A few lay minute eggs on the food plants of their hosts, and the eggs are later ingested by a host.

Exoristinae are defined by a combination of a number of characters, but none of the characters are unique to the subfamily.

On the antennae the bristle (arista) is usually bare. There are almost always three intra-alar bristles (setae).

The front-most plate on the underside of the thorax (prosternum) is hairy.

On the abdomen, the upper plates (tergites) cover or almost cover the plates on the underside (sternites). On males, the sixth tergite is more or less divided longitudinally or is completely reduced.

Sources

24, 27, 30, 82.

This subfamily was formerly called Goniinae. It was determined that the name Exoristinae has priority, and the subfamily name was changed to that in 1999.

Location: Woodbury, Minnesota