The main median nervure, and usually also the sub-costal become united with the radial, while the branches of radial, median and cubital nervures pursuing a transverse or recurrent course across the wing, divide its area into a number of areolets or " cells," that are of importance in classification.
The fore-wing also has no stigma, and the whole wing is almost destitute of nervures and areolets, while the pronotum does not reach back to the tegulae, and the feelers are elbowed (fig.
The ten thousand known species included in this group agree with the Cynipoidea and Chalcidoidea in the position of the ovipositor and in the jointed trochanters, but are distinguished by the fore-wing possessing a distinct stigma and usually a typical series of nervures and areolets (figs.
The Myrmeleonidae are large insects with short clubbed feelers on their prominent heads, and two pairs of closely similar net-veined wings, with regular oblong areolets at the tips.
The same is the case with the allied Ascalaphidae, which are distinguished from the Myrmeleonidae by their elongate feelers - as long as the body - and by the irregular apical areolets of the wings.