Microdiprion pallipes - Least Pine Combhorn

There are few records currently recognised, all of which are from central and northern Scotland except for outliers at Hafren Forest (mid Wales) in 1973 and near Coventry in 1987. The pattern of records is more suggestive of a species which is easily overlooked rather than declining (Musgrove, 2022).

Mainly black with pale legs. Abdomen shining. The scutellum is longer than broad and acutely angled in front. Claws without an inner tooth.

Larvae feed on pines, especially Scots pine. Small trees up to 1.5m are preferred. Larvae feed in groups on young needles initially, then moving on to old needles. Microdiprion pallipes can be bivoltine in years with favourable weather and the two generations can overlap.

Jump to other Diprionidae genera and species

Size: 5 - 7mm

GB IUCN Status: Near Threatened
GB Rarity Status: Nationally Rare

Distribution: England, Scotland, Wales

Flight period: Univoltine May to June, or bivoltine May to June, July to August in warmer years

Plant associations: Pinus spp., especially sylvestris (pines, especially Scots Pine)

References:

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

Mallach, N. 1974: Zur Kenntnis der Kleinen Kiefern-Buschhornblattwespe, Diprion (Microdiprion) pallipes (Fall.) (Hym., Diprionidae). Teil 3: Populationsökologie. - Zeitschrift für angewandte Entomologie, Berlin 75: 337- 380

Musgrove, A.J. 2022. A review of the status of sawflies of Great Britain - Phase 1: families other than Tenthredinidae. Natural England, unpublished

Olofsson, E., 1994. Biology and outbreaks of Microdiprion pallipes (Hymenoptera; Diprionidae) in Sweden, Studia Forestalia Suecica, vol. 193, Uppsala