Phaeostigma notata
Phaeostigma notata is the largest snakefly found in the British Isles. It has an elongated pronotum, four membranous wings and long needle-like ovipositor in females. It has a dark black body. The legs have a black femora with the tibia and part of the tarsi being a red-brown colour. The abdomen has pale yellow markings. The pterostigma is present on all four wings, and is a pale dark brown in colour, sometimes appearing black. It has a body length of 10–15mm and a wingspan of 20–30mm.
It is widespread in England and Wales, but as yet no records from Scotland or Ireland.
The species can be differentiated from other raphidiopterans from the British Isles by characters in the forewing: Basal vein of Cell 1 (A) basal to the end of the Pterostigma. The Pterostigma appears to start approximately 1/3 or 1/2 way along Cell 1 (B). Distal vein of Cell 1 (B) goes beyond the end of the Pterostigma. Vein R continues past the Pterostigma forking at the wing edge (C). Pterostigma is a dark brown colour, usually containing at least 2 crossveins (D). Costal space (E) with approximately 12 crossveins.
Note: A European species, found in Scandinavia and Central Europe also shares many of these characters, and indeed would key out here using Plant (1997). There is a good possibility this species could be found in Scotland. This species is Raphidia ophiopsis (see inlay on image). It can be differentiated from P. notata by possessing less than 10 crossveins in the Costal space (F) and having a single crossvein in the Pterostigma (G). Any specimen that seems not to fit comfortably in Phaeostigma notata should be sent for checking.
Woodland and occasionally gardens; often associated with oaks.