A picture of a Scorpion Fly
Photo by:
L. West/Photo Researchers, Inc.
Mecoptera, group of primitive four-winged insects that includes the scorpion fly and the hanging fly. Mecoptera is not a true two-winged fly but rather an ancient insect group that first appeared during the Permian period (290 to 240 million years ago). Although mecoptera are found worldwide, they were once far more diverse than they are today. In fact, there are more described fossil species than living species.

Mecoptera has four long and narrow wings with many veins, slender legs, long antennae, and an elongated head with a beaklike snout, or rostrum. It is somewhat similar in appearance to the crane fly except that crane flies have only two wings. Scorpion flies are named for the males whose external reproductive organs are bulblike and carried over the back like a scorpion's tail. Scorpion flies are scavengers in forests where both adults and larvae feed on dead insects. Hanging flies are named for their peculiar method of hunting. At night they hang from vegetation by their front pair of legs and catch insects with their specially adapted hind legs.

The mecoptera male attracts females with a chemical scent or pheromone. He presents the female a food gift of a dead insect or a salivary mass and mates with her as she is eating. The food gift needs to be large enough to ensure sufficient time to mate, which can take up to 20 minutes and requires at least 5 minutes for adequate transfer of sperm. If the female finds the gift unsatisfactory, she may fly off seeking another male. Males will often try to steal insect food gifts from other males. Alternatively, instead of offering a food gift, the male will sometimes grab the female and forcibly mate while holding her down with his wings. Mecoptera larvae are caterpillarlike and are generally found in leaf litter. Larvae undergo their transformation into adults just beneath the soil surface and feed on dead and decaying organic matter.

Scientific classification: There are nine families in the order Mecoptera found throughout North America, South America, and Australia. True scorpion flies are members of the family Panorpidae and hanging flies are members of the family Bittacidae. The name mecoptera is from the Greek for long wing.

Share this page with your friends!


Do you like this article?
Support our project, so we could place more interesting information here! Click here for details.