As with all Tenthredopsis species Tenthredopsis litterata 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. This is the largest of the six British and Irish species.
In the female the hypopygium has a very large appendage, dark and sclerotised in the centre and with broad, skin-like, pale side parts. It is incised apically to a quarter to one-third of its length. This distinctive hypogydium appears like an inverted black "Y". In the darkest females the whole upper head, thorax (including gthe scutellum) and abdomen are black.
Males of this species can be distinguished by the penis valves which have very long needle-like projections visible from above without dissection.
Larvae feed on grasses.
Size: 11 - 12mm
Distribution: England, Scotland, Wales
Flight period: May to July
Plant associations: Gramineae including Dactylis glomerata (grasses including cock's-foot)
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