Please refer also to the following links for details on this group:
Raphidiidae = Link 1
Carpenter (1936) gave an early review regarding the behavior of raphidids, most of which were European species. Adults of Raphidia notata F. were found to feed readily on aphids in the laboratory. Larger insects such as flies and beetle larvae were attacked only after they had been injured and were thus unable to put up a defense. Adult Agulla unicolor Carp. fed on freshly killed Chironomidae. They showed a definite cannibalistic tendency also.
Raphidiidae is a small family with less than 100 described species. There are 17 species of Raphidia known in North America. They are mainly palearctic in distribution, but are found on all continents except Australia. Important characters of these "snake flies" include an elongated prothorax with forelegs at the posterior end; front legs not raptorial; forewing R-s with more than two branches; ocelli are absent; ovipositor is exserted and antennae are setiform. The wings of adults vary from 6-17 mm long, and females are somewhat larger than males.
Larvae and adult raphidiids are predaceous on soft-bodied insects such as lepidopterous larvae and aphids. Their eggs are laid in clusters in crevices in bark and the larvae live under bark, in decaying wood, or in similar protected places. They pupate in an oval cell beneath bark or in decaying wood. The life cycle may take several years. One species was introduced into New Zealand from southern California in 1890 as a predator of black scale eggs, with limited success (Clausen 1940/62).
Carpenter, F. M. 1936. Revision of the nearctic Raphidiodea (recent and fossil). Proc. Amer. Acad. Arts & Sci. 71(2): 89-157.