Recorded widely across all of mainland Britain (Musgrove, 2023).
Dolerus madidus is very similar to Dolerus uliginosus. The distinction between the two species is to some degree subjective. Uliginosus supposedly has more coarse puncturation on the mesepisternum than does madidus. According to Haris (2000), the head in uliginosus is parallel to "slightly dilated" behind the eyes as opposed to converging in madidus. He further notes that the occipital furrows are deep and long in uliginosus as opposed to very short in madidus.
Male: An orange banded abdomen with other parts black.
Female: The body is predominantly orange on top contrasting with the black head, black scutellum and black legs. The female is similar to Dolerus aericeps and Dolerus triplicatus. In madidus the legs are entirely black, whereas aericeps has red about the knees. Also, the front lobe of the mesonotum is always red in madidus but in aericeps it is often entirely black, though this is not always the case. The scutellum in madidus is black, whereas it is red in triplicatus.
Larvae feed on Juncus.
Size: 8 - 10.5mm
GB IUCN Status: Least Concern
GB Rarity Status: None
Distribution: England, Scotland, Wales, Ireland
Flight period: March to June
Plant associations: Juncus sp. (rushes)
Benson, R.B., 1952. Handbooks for the Identification of British Insects. Hymenoptera, Symphyta, Vol 6, Section 2(a-c), Royal Entomological Society, London
Haris, A., 2000. Study on the Palaearctic Dolerus Panzer, 1801 species (Hymenoptera: Tenthredinidae). Folia entomologica hungarica, 61(1), pp.95-148.
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. 2023. A review of the status of sawflies of Great Britain - Phase 2: The Athaliidae and the Tenthredinidae (excluding Nematinae). Natural England, unpublished