Gilpinia hercyniae - European Spruce Combhorn

A non-native species, appearing in spruce plantations from 1906 onwards. Records remained at fairly low levels, although widespread in southern England, until a major outbreak in Wales in the 1970s. This subsided and there have been no subsequent outbreaks. There are few records from northern England and none to date from Scotland. Since 1977 there are only two dated records, from 2000 and 2011, both in Surrey. It seems highly plausible that the species remains present at low density in spruce plantations (Musgrove, 2022). This species is parthenogenic in Britain with males being exceedingly rare. The female's inner apical spur of the hind tibia is shaped like a scale. Apex of the sawsheath in dorsal view is much broader than the apical breadth of the hind tibia. The underside of the thorax is dark. The costa of the fore wing is yellow and the stigma is yellow with a dark margin and base.

Larvae feed singly on spruces, especially Norway Spruce. They oviposit and feed on older needles.

Jump to other Diprionidae genera and species

Size: 6 - 8mm

GB IUCN Status: Data Deficient
GB Rarity Status: Nationally Rare

Distribution: England, Wales

Flight period: Bivoltine, May to June, and sometimes July to September

Plant associations: Picea spp., especially excelsa (Norway Spruce).

The National Biodiversity Network records are shown on the map below. (See terms and conditions)

References:

Benson, R.B., 1952. Handbooks for the Identification of British Insects. Hymenoptera, Symphyta, Vol 6, Section 2(a-c), Royal Entomological Society, London

Billany, D. J. & Brown, R. M. 1977: The geographical distribution of Gilpinia hercyniae Hymenoptera: Diprionidae in the United Kingdom. - Forestry, Oxford 50(2): 155-160

Billany, D. J.; Borden, J. H. & Brown, R. M. 1978: Distribution of Gilpinia hercyniae (Hymenoptera Diprionidae) eggs within sitka spruce trees. - Forestry, Oxford 51(1): 67-72

Billany, D. J.; Carter, C. I.; Winter, T. G. & Fielding, N. J. 1983: The effects of climate and parasites on Gilpinia hercyniae (Hartig) (Hymenoptera: Diprionidae) in Britain. - The Entomologist's Monthly Magazine, Brightwood 119(1428-1431): 117- 120

Buse, A. 1977: The importance of birds in the dispersal of nuclear polyhedrosis virus of European spruce sawfly, Gilpinia hercyniae (Hymenoptera: Diprionidae) in mid-Wales. - Entomologia experimentalis et applicata, Amsterdam 22(2): 191-199

Finlayson, L. R. & Finlayson, T. 1958: Notes on parasites of Diprionidae in Europe and Japan and their establishment in Canada on Diprion hercyniae (Htg.) (Hymenoptera: Diprionidae). - The Canadian Entomologist, Ottawa 90(9): 557-563

Goulet, H. 1981: New external distinguishing characters for the sawflies Gilpinia hercyniae and G. polytoma (Hymenoptera: Diprionidae). - The Canadian Entomologist, Ottawa 113(8): 769-771

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

Reeks, W. A. 1941: On the taxonomic status of Gilpinia polytoma (Htg.) and G. hercyniae (Htg.) (Hymenoptera, Diprionidae). - The Canadian Entomologist, Guelph 73(10): 177-188