Neuroptera of the family Sialidae, the alderflies, are dark colored and have long, thread-like antennae. The females do not have ovipositors but nevertheless use their crude genital appendages to lay hundreds of eggs. The eggs are stacked on the leaves of marsh reeds.

The eggs are extremely vulnerable to at- tacks from the larvae of several species of Hymenoptera. Some wasps lay their eggs on top of the alderfly eggs. The wasp larvae hatch before the young alderflies. The emerg- ing wasps thus have quite easy pickings, and they feed voraciously on the alderfly eggs.

The alderfly larvae that survive drop off the marsh reeds. For a time, they hunt their prey in the mud or slime along the water's edge. After a while, however, they work their way along the bottom to the deeper parts of lakes and streams. Some alderflies have been found in water at depths much greater than 30 feet.


INDEX : Insects     September 16, 2008 01:11:22 PM