Tenthredopsis scutellaris (Fabricius, 1804)

Tenthredopsis scutellaris

As with all Tenthredopsis species Tenthredopsis scutellaris is variable in colour. The description given here follows Blank and Ritzau 1998 but it should be noted that British specimens may differ in colour from continental counterparts.

In the female the abdomen is broadly red, with the sixth tergite red on at least the basal margin. The hind tarsi are mostly dark but if the middle segments are pale, the first and fifth segments are usually also significantly pale. The hind coxae with a large whitish spot on the lateral face. The hypopygium centrally is triangular and only slightly indented at the apex (as for nassata).
The male cannot be reliably distinguished from Tenthredopsis scutellaris. The mesepisternum is often darkened with the pectus usually completely black. The hind tarsi are more or less uniformly light or dark. Dried specimens have a midline keel on the eighth tergite, which often reaches the base of the tergite. On either side of the keel there is a deep and somewhat oval-shaped depression, at least from the posterior margin to the middle and often to the base of the tergite.

Larvae feed on grasses.

 

Size: Female: 8.5 - 11mm, male: 8 - 11mm.

Status: Widespread

Distribution: England, Scotland, Ireland

Flight period: May to August

Plant associations: Gramineae (grasses).

References:

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

Blank, S.M. and Ritzau, C., 1998. Die Tenthredopsini Deutschlands (Hymenoptera: Tenthredinidae). Pflanzenwespen Deutschlands (Hymenoptera, Symphyta). Kommentierte Bestandsaufnahme, pp.227-246.

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