Euura ribesii (Scopoli, 1763)

Prous, Marko, Liston, Andrew, Monckton, Spencer K., Kramp, Katja, Vårdal, Hege, Vikberg, Veli, Heibo, Erik & Mutanen, Marko, 2025, West Palaearctic species of Euura Newman, 1837 (Hymenoptera, Tenthredinidae), European Journal of Taxonomy 977, pp. 1-377 : 198

268 Euura ribesii group

Black or dark brown pterostigma, short valvula 3, and structure of lancet and penis valve enables recognition of the group among the other Euura . Of the species of Euura with a black pterostigma, only E. spiraeae has a similar type of lancet as in the E. ribesii group. In E. spiraeae , the setae of the lancet are hair-like and the basalmost annulus is narrower (compared to height) than in the E. ribesii group (setae spine-like). Only E. vastatrix , a rare species in Eastern Europe, seems to have a pale pterostigma, in which case the spine-like setae of the lancet can be used to distinguish the females from the species with a similar type of lancet ( papillosa group, and E. hypoxantha and E. jugicola of the myosotidis group). Euura ribesii group females lay eggs on the undersides of leaves ( Viitasaari 1980), in contrast to most other Euura that lay eggs inside the leaf or petiole tissue. This habit of egg-laying is shared with E. spiraeae ( Robbins 1927; Hara et al. 2022) and the papillosa group ( Urban 2001) with a similar type of lancet. Euura hypoxantha and E. jugicola ( myosotidis group) also have a similar type of lancet, but egg laying habits of these species are not known. Seven species are recognized. Most common are E. ribesii and E. leucotrocha , in Central and Western Europe also E. similator . The other species are rarely encountered.