Euura styx (Benson, 1958)

197 Euura styx (Benson, 1958)

Figs 212 View Figs 210–212 , 443–444 View Figs 436–449

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 . GoogleMaps

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.