One of three small species formerly included in the Rhogogaster picta group. All three have bicolorous blue-green/black stigma. Cytisogaster chambersi has both male and female genders. The hind tibia are lined with black on the anterio-dorsal face. Facial markings and saw teeth are diagnostic (see Benson). Most of the stigma is pale.
Larvae feed on fairy flax. Several eggs are lain into the upper surface of leaves of this small plant causing obvious blisters. Larvae nibble at leaves. There are three or four larval instars prior to the prepupal stage and larvae feed for 30 to 50 days. The prepupa burrows without delay into the soil.
Size: 6 - 8.5mm
Status: Widely distributed
Distribution: England, Scotland, Wales
Flight period: May to July
Plant associations: Linum catharticum (fairy flax)
The National Biodiversity Network records are shown on the map below. (See terms and conditions)
Benson, R.B., 1952. Handbooks for the Identification of British Insects. Hymenoptera, Symphyta, Vol 6, Section 2(a-c), Royal Entomological Society, London
Chambers, V. H. 1951: The larva and foodplant of Rhogogaster chambersi Benson (Hym., Tenthredinidae). - The Entomologist's Monthly Magazine, Fourth Series, London 87(12): 202-205
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