Mantidfly

Mantidflies are insects in the family Mantispidae. They are small to moderate-sized insects in the order Neuroptera. There are many genera with around 400 species worldwide, especially in the tropics and subtropics. Only 5 species of "Mantispa" occur in Europe.
Description and ecology.
Some mantidflies are wasp mimics, but most are brownish with green, yellow and sometimes red hues. 
They get their name from their mantis-like appearance, as their spiny "raptorial" (raptor-like) front legs are modified to catch small insect prey and are very similar to the front legs of mantids. The adults are predatory insects that are often nocturnal, and are sometimes attracted by porch lights. They have four membranous wings which may sometimes be patterned (especially in wasp mimicking species) but are usually clear. Adult mantidflies are predators of suitably sized insects, which they catch as mantids do. Mantidflies are active hunters, but as with other Neuroptera, they are cumbersome fliers.
Their larvae are either parasitoids or predators. Subfamily Symphrasinae larvae are parasitoids on bee, wasp or scarab beetle larvae. Larvae of the subfamily Calomantispinae are predators of small arthropods. 
Larvae of the subfamily Mantispinae seek out female spiders or their egg sacs which they then enter; the scarab-like larvae then feed on the spider eggs, draining egg contents through a piercing/sucking tube. Then they pupate in the egg sac.