Acantholyda erythrocephala, the red-headed pine sawfly, also called the pine false webworm, is an easy to recognise species. The female is a glossy black insect with a blueish reflection and a striking red, or orange-yellow head. The male is similarly coloured but only the face and fore-tibiae are orange-yellow.
Females lay eggs in rows on the previous year's pine needles and the larvae spin silk tubes from which they feed. Once mature, the larvae fall to the ground and overwinter as a prepupa in the leaf litter.
Size: 10 - 12mm
Distribution: England, Scotland
Flight period: April to June
Plant associations: Pinus spp. (pines)
The National Biodiversity Network records are shown on the map below. (See terms and conditions)
Benson, R.B., 1952. Handbooks for the Identification of British Insects. Hymenoptera, Symphyta, Vol 6, Section 2(a-c), Royal Entomological Society, London
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
Viitasaari, M. ed., 2002. Sawflies (Hymenoptera, Symphyta), I: a review of the suborder, the Western Palaearctic taxa of Xyeloidea and Pamphilioidea (Vol. 1). Tremex Press.