Rhogogaster chlorosoma (Benson, 1943)

Rhogogaster chlorosoma

Frequently encountered though probably not as common as Rhogogaster scalaris. This species is very similar to scalaris. It is generally less black-marked on the abdomen but pale scalaris specimens overlap with dark chlorosoma species. Males of the two species can be determined by the length of the plantar lobes (tarsal pulvilli) on the hind tarsi. In chlorosoma males the plantar lobe of one tarsal segment is about one-half the length of the following tarsal segment. In scalaris, it is one-third. In females, there is some crossover in this characteristic.
The black markings on the top of the head form an enclosed figure-of-eight.

Larvae are recorded from a broad range of trees and herbs including alders, poplars, willows, rowans and meadowsweet.

 

Size: 10 - 13mm

Status: Common

Distribution: England, Scotland, Wales

Flight period: May to July

Plant associations: Polyphagous. Alnus spp., Populus spp., Salix spp., Sorbus spp. and Filipendula ulmaria (various trees and herbs)

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

Taeger, A. and Viitasaari, M., 2015. European Rhogogaster s. str., with notes on several Asian species (Hymenoptera: Tenthredinidae). Zootaxa, 4013(3), pp.369-398.