Monardis plana (Rose-bud sawfly)

This species was discovered new to Britain in 2003, in dune habitat near Bridgend in south Wales, where numerous individuals were recorded (Gibbs 2006). There were no further records until targeted survey of the same site in 2023 confirmed the continuing presence of the species here (Musgrove, 2023).

Adults closely resemble Cladardis spp. but can be distinguished by the presence of robust spines on the sawsheath. Another rose feeder, Ardis pallipes, also has spines on the sawsheath. However, Monards plana lacks the deep pits around the eye orbits that characterise Ardis spp.

Monardis plana larvae feed within the unopened folds of leaflets in the buds of burnet rose before burrowing apical shoots and flower stalks.

Jump to information on the genus Monardis

Size: 6 - 7mm

GB IUCN Status: Vulnerable
GB Rarity Status: Nationally Rare

Distribution: Wales

Flight period: April to May

Plant associations: Rosa spinosissima (Burnet Rose)

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

Gibbs, D., 2006. Rose bud sawfly, Monardis plana (Klug)(Hymenoptera: Tenthridinidae), new to Britain, discovered in South Wales. British Journal of Entomology and Natural History, 19(2), pp.105-108.

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 Natural England, unpublished