Eutomostethus luteiventris

Recorded widely across all of mainland Britain (Musgrove, 2023).

One of the black and orange species. The thorax, head and wings are black. The legs are dark at the bases and tarsi. The abdomen, femora and tibia are orange. Only females are known in Britain and Ireland.

Eutomostethus luteiventris early instar larvae feed on the inside the stems of soft rush and can have more than one per stem. Frass remains inside the stem. Growing larvae emerge from the stem around the third instar and then graze the outer surface of the stem. 

Jump to other Eutomostethus species

Size: 5 - 7 mm.

GB IUCN Status: Common
GB Rarity Status: Common

Distribution: England, Scotland, Wales, Ireland

Flight period: April to July

Plant associations: Juncus effusus (soft rush)

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

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 Natural England, unpublished