Sialidae, Osmylidae, Sisyridae

Abstract

Alderflies (family Sialidae) are blackish or brownish, soft-bodied insects of 10–16 mm length (Figs. 295/1 and 299/6). The broad head bears long filiform antennae. At rest, the smoke coloured wings are held roof-like above the body. A conspicuous peculiarity of the wings is the dark nervation. Adult alderflies are common waterside insects of the early summer. They fly quite rarely; they are mostly found hidden amongst the waterside vegetation instead. The lifespan of the males is merely some days, whilst females live for 1–2 weeks.