Cephus nigrinus - Wood Stem-sawfly

Quite widespread as far north as Yorkshire, although decidedly local in eastern areas, the south-west and much of Wales (Musgrove, 2022). Easily recognised as the only Cephus species with an all black abdomen, although occasionally British specimens have yellow flecks on the lateral margins of some tergites. The sawsheath is set in a straight line with the oblong plate. Cephus nigrinus appears to be a woodland species in the Britain.

 Larvae feed by boring into Smooth Meadow-grass.

Jump to other Cephidae

Size: 7 - 10mm

GB IUCN Status: Least Concern
GB Rarity Status: None

Distribution: England, Wales

Flight period: May to July

Plant associations: Poa pratensis (Smooth Meadow-grass)


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

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 Natural England, unpublished