Stoneflies

StoneStoneflies, belonging to the Insect order Plecoptera, are so called because the adults of the larger species may often be encountered walking, and hiding, amongst the rocks on the shore after emerging from rivers and streams.   Many of the smaller species are active flyers and may also be found on tree trunks and amongst bankside vegetation.   The scientific name refers to the complex pattern of venation in the wings which, in some species, resembles braiding when the wings are folded along the back when at rest.   Adults may be fairly short lived as many of them are not known to feed; although they do drink; but there is evidence (shown by gut content analysis) that some species do feed on lichens and pollen.  The juvenile stages, at least of the larger species, may take up to three years to grow to maturity.   Both adults and mature juveniles can be identified to species using the keys in Hynes (1993).

Hynes, H.B.N. (1993). A key to the adults and nymphs of the British Stoneflies (Plecoptera) with notes on their Ecology and Distribution. Scientific Publications of the Freshwater Biological Association No. 17.

Stoneflies are occassionally found in light trap by-catches. Some can be identified from qood quality photographs, but, most require more detailed examination, usually on deceased specimens, in order to identify them reliably to species. Photographs of the relevent characters will be necessary if records are to be veritied on iRecord.