Euura infirma

116 Euura infirma (Förster, 1854) Figs 105, 339 Nematus infirmus Förster, 1854a: 316–318. Lectotype designated by Taeger & Blank (1998). Nematus subaequalis Förster, 1854a: 305–307. Lectotype designated by Taeger & Blank (1998). Synonymy by Taeger & Blank (1998). Diagnosis The females are most similar to E. gehrsi, E. annulata, and E. oehlkei, but can be distinguished based on lancets which are ventrally concave and have serrulae present also on basal-most annuli (ventrally slightly convex in E. gehrsi and E. annulata and basal 2–3 annuli without serrulae in E. gehrsi, E. annulata, and E. oehlkei). Valvula 3 is also narrower in dorsal view than in E. gehrsi, E. annulata, and perhaps E. oehlkei. Male penis valves are clearly distinguishable from the other Euura. Pseudoceps of the penis valve is apically filament-like, which is otherwise only seen in a few species of Euura that have bifid claws (small subapical tooth in E. infirma). Female 3.7–3.9 mm. Head slightly to extensively pale around eyes; labrum, clypeus, and supraclypeal area pale; thorax black; pronotum black or posteriorly slightly pale; tegula pale; pterostigma pale; metafemur extensively pale; metatibia pale; hind tarsus black; abdomen black; valvifer 2 pale; valvula 3 black or brown, in dorsal view narrow and with acute apex. Type material examined Lectotype Nematus infirmus GERMANY – Nordrhein-Westfalen • ♂; Aachen area; 50.77° N, 6.09° E; ZSM, GBIF-GISHym 3303. Lectotype Nematus subaequalis GERMANY – Nordrhein-Westfalen • ♀; Aachen area; 50.77° N, 6.09° E; ZSM, GBIF-GISHym3445. Host plants Bistorta officinalis (Macek et al. 2020; rearings by Alexey Zinovjev). Genetics COI Based on 3 specimens, maximum within-species distance is 0.46% and the nearest neighbours, diverging by a minimum of 4.86%, are Euura polaris and E. poppii. Nuclear Based on 2 specimens, maximum within-species distance is 0% (0.33% based on haplotypes of individual females). The nearest neighbour, diverging by a minimum of 0.92%, is Euura gehrsi. Distribution and material examined Palaearctic. Specimens studied are from France, Germany, Italy, and Russia. Euura infirma should be removed from the Finnish list, because the records probably refer to E. gehrsi.