Pristiphora wesmaeli - Wesmael's Larch Sawyer
Pristiphora erichsonii group

Scattered records north to southern Scotland. Includes the formerly recognised P. glauca which seems indistinguishable (M. Prous pers. comm.) All conifer-feeding sawflies seem poorly recorded. However, this one seems to have seen a particular drop-off in records recently compared to former years (Musgrove, 2024).

This species is so similar to Pristiphora glauca that adults cannot often be distinguished. Even the genitalia are hard to distinguish. The later emergence of adults and later larval feeding period is thought to be a more reliable method of distinguishing between the two species.

Pristiphora wesmaeli larval food plant is European larch and Japanese and Dahurian larch were introduced.

Jump to other species of Pristiphora

Size: 6.0 - 7.5mm

GB IUCN status: Endangered
GB rarity status: Nationally Rare

Distribution: England, Scotland, Wales, Ireland

Flight period: May to July

Plant associations: Larix decidua, Larix kaempferi and Larix gmelinii (European larch, Japanese larch and Dahurian larch)

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

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 Natural England, unpublished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., Kramp, K., Vikberg, V. and Liston, A., 2017. north-Western Palaearctic species of Pristiphora (hymenoptera, tenthredinidae). Journal of Hymenoptera Research, Vol. 59