Euura styx

197 Euura styx (Benson, 1958) Figs 212, 443–444 Pachynematus styx Benson, 1958b: 301–303. Diagnosis The mostly black mesepisternum seems to distinguish E. styx from the others in the group. Most of the studied specimens from Finland have a dark brown pterostigma with a small pale area at the base, but the holotype of styx Benson and a specimen from Oulu (ZMUO.033769) have a uniformly yellowish pterostigma like the other species of the group. The specimen of E. styx with a yellowish pterostigma is not genetically different from those with a dark pterostigma. Based on the specimen NG.1551 (432 bp of COI is identical to all the other sequenced specimens of styx and clearly different from the other species) and a paratype of styx, the penis valve is most similar to E. pallescens. Ventroapical lobe of paravalva is asymmetrical (dorsal margin straight and ventrally convex) in E. styx, but more or less symmetrical in E. pallescens. Type material examined Holotype Pachynematus styx GERMANY – Niedersachsen • ♀; Sieber; 51.70° N, 10.43° E; 600 m a.s.l.; 1955; W. Thalenhorst leg.; reared ex larva from Picea abies; BMNH, B.M.TYPEHYM.1.791. Host plants Picea abies (Benson 1958b). One generation per year. Genetics COI Based on 4 specimens, maximum within-species distance is 0.15% and the nearest neighbour, diverging by a minimum of 1.98%, is Euura pallescens group specimen DEI-GISHym80693 from Primorsky Krai. Nuclear Based on 4 specimens, maximum within-species distance is 0.06% (0.18% based on haplotypes of individual females). The nearest neighbour, diverging by a minimum of 0.71%, is Euura montana. Distribution and material examined Palaearctic. Specimens studied are from Finland and Germany.