Fenusella nana

Recorded widely across much of mainland Britain, as well as from Skye (Musgrove, 2023).

Antennae with segment 8 twice as long as broad. Female mainly piceous black with a white labrum and tegulae and off-white knees, tibiae and tarsi of all legs. The male is mainly yellow with white on the tegulae and the outer edges of pronotum and otherwise mostly black or piceous. Frons with a distinct carina enclosing a supra-antennal field below and almost enclosing a frontal area above (open at the top).

Fenusella nana larvae feed in mines in the leaves of birches especially downy birch. Mines begin at a vein on the leaf edge and the entrance is plugged with frass. Larvae are green initially but turn more orange at maturity.

Jump to other Fenusella species

Size: Approx. 4 - 4.5mm

GB IUCN Status: Least Concern
GB Rarity Status: None

Distribution: England, Scotland, Wales, Ireland

Flight period: May to June

Plant associations: Betula spp. esp. Betula pubescens (birches esp. downy birch)


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

DeClerck, R. A. & Shorthouse, J. D. 1985: Tissue preference and damage by Fenusa pusilla and Messa nana (Hymenoptera: Tenthredinidae), leaf-mining sawflies on white birch (Betula papyrifera). - The Canadian Entomologist, Ottawa 117(3): 351- 362

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. 2023. A review of the status of sawflies of Great Britain - Phase 2: The Athaliidae and the Tenthredinidae (excluding Nematinae). Natural England, unpublished