Xyela longula - Long Daggertail
The three species of Xyela can be difficult to identify from single specimens due to the few available characteristics. A little-known species, with just two clusters of records around Aviemore in the 1940s, and the north side of the Dornoch Firth in the 1990s (Musgrove, 2022).
In this species, males and females are piceous and more or less marked with yellow. The wings are brownish infuscate. The sawsheath is sharply pointed.
Xyela longula larvae feed on the developing pollen in immature male cones causing the cones to become bent out of shape. Several larvae may feed in each cone. Larvae emerge and drop to the ground to pupate. They hatch the next spring or may enter diapause for two to three years. The pupa has free legs and can run around on the surface before the adult emerges from the exuvia.
Size: approx. 3.5 - 4.5mm
GB IUCN Status: Data Deficient
GB Rarity Status: Nationally Rare
Flight period: Mid-March to late-April
Plant associations: Pinus sylvestris (Scots Pine).
Blank, S.M., 2002. The Western Palaearctic Xyelidae (Hymenoptera), pp. 197-233. In: Viitasaari, M. (editor), Sawflies (Hymenoptera, Symphyta) I. A review of the suborder, the Western Palaearctic taxa of Xyeloidea and Pamphiloidea, Tremex, Helsinki
Liston A, Knight G, Sheppard D, Broad G, Livermore L (2014) Checklist of British and Irish Hymenoptera - Sawflies, ‘Symphyta’. Biodiversity Data Journal 2: e1168. https://doi.org/10.3897/BDJ.2.e1168
Musgrove, A.J. 2022. A review of the status of sawflies of Great Britain - Phase 1: families other than Tenthredinidae. Natural England, unpublished