NON_GROUPED

Euura spiraeae - Aruncus Sawfly

Nematus spiraeae Zaddach, 1883
Pteronidea subflava Lindqvist, 1958

North to northern Scotland. Non-native but recorded in Britain since 1924 and remains frequent in gardens where the foodplant (which is native to continental Europe) is grown (Musgrove, 2024).

Males are extremely rare. Abdomen always partly pale below, but mostly black above, and cerci not reaching hack as far as of the narrow sawsheath. The mesopleura and the orbits behind the eyes are mainly black as are the front and middle lobes of the mesonotum.

Euura spiraeae ova are deposited in clusters on the underside of leaves between side veins. The larvae feed gregariously on buck's-beard. Ova hatch after one or two weeks and the larvae reach maturity after two to four weeks.  The first generation cocoon either above ground or burrow and adults can emerge after as little as five days though two to three weeks is more normal. 

Size: Female: 5.0 - 6.0mm.

GB IUCN status: Least Concern
GB rarity status: None

Distribution: England, Scotland, Wales, Ireland

Flight period: Multivoltine, April to September (three or four generations)

Plant associations: Aruncus dioicus (buck's-beard)

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

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

Moisan-De Serres, J.; Smith, D. R. 2017: Nematus spiraeae Zaddach (Hymenoptera: Tenthredinidae) A Palearctic Sawfly on Aruncus (Rosaceae) New to North America. - Proceedings of the entomological Society of Washington, Washington 119(3): 459-463.

Muche, W.H., 1974. Die Nematinengattungen Pristiphora Latreille, Pachynematus Konow und Nematus Panzer (Hym., Temthredinidae). Deutsche Entomologische Zeitschrift, 21(1/3), pp.1-137.

Musgrove, A.J. 2024. A review of the status of sawflies of Great Britain - Phase 3: The Tenthredinidae (subfamily Nematinae). Natural England, unpublished

Prous, M., Liston, A., Kramp, K., Savina, H., Vårdal, H. and Taeger, A., 2019. The West Palaearctic genera of Nematinae (Hymenoptera, Tenthredinidae). ZooKeys, 875, p.63-127

Robbins, J. C. 1927: A rare sawfly. Notes on the Life-History and Distribution of Pteronidea spiraeae, Zaddach (Hymenoptera, Tenthredinidae). - The London Naturalist. The Journal of the London Natural History Society., London (20): 11-16

Rossum, A. J. van 1904: Pteronus spiraeae Zdd. in Nederland. - Entomologische Berichten, Amsterdam 1(19): 174-175.