Insect guide > Flies > March Flies

March Flies

(Family Bibionidae.)
The flies of this family are not especially interesting. They are of medium size and are rather thick-bodied and rather hairy but are weak fliers. Their wings are frequently smoky. Some species, as Scatopse, are very small. There seems to be nothing especially interesting about the group, although more than three hundred species are known.

The larvae are cylindrical and have transverse rows of bristles and the head, which is rarely obvious in dipterous larvae, shows eyes. They feed upon excremental or vegetable substances and are said to attack the roots of growing grass. One of our commonest species is Bibio albipennis.

This species sometimes occurs in enormous numbers. In the spring of 1891, according to Osborn, it abounded in parts of Iowa and was erroneously reported as doing much damage to vegetation. In this form the wings are white, quite contrary to the general rule in the family. Other species are of a deep red color with dark wings. The larvae of some species of this family have been found on the surface of snow.

The flies of the genus Scatopse breed in decaying vegetable material, in sewers, and in human excreta. Scatopse pulicaria is common on our windows at certain seasons of the year and, as it is an excrement fly, is a dangerous inhabitant of houses.