Alderflies
In early texts the Megaloptera were included within the Neuroptera, together with the Raphidioptera, but they have long been recognised as a distinct order.
The monophyly of this group of three orders, sometimes termed the Neuropterida, is not in question, but the exact relationships between them are yet to be fully resolved.
Sialis lutaria Credit Roger KeyAdult Megaloptera have broad flattened heads with biting mouthparts, and two pairs of very similar wings; all the larvae are freshwater predators.
Worldwide there are around 330 known species in 2 families; in Britain there are 3 species in 1 family.
Identification help
