Euura dispar (Zaddach, 1876)

Prous, Marko, Liston, Andrew & Mutanen, Marko, 2021, Revision of the West Palaearctic Euura bergmanni and oligospila groups (Hymenoptera, Tenthredinidae), Journal of Hymenoptera Research 84, pp. 187-269 : 187

Euura dispar (Zaddach, 1876)

Figs 4 , 8A , 11B , 15 , 24C-E

Nematus dispar Zaddach, 1876: Plate II(5), 5. Type locality: Heubude (according to Brischke 1884) [Poland, now part of Gdansk] (ST). Type material probably destroyed ( Blank and Taeger 1998).

Pteronidea pseudodispar Lindqvist, 1969: 242-245. Type locality: Finland, Helsinki, Munksnäs (HT). Syn. nov.

Similar species.

Most similar species are E. viridis and E. glutinosae , from which it possibly differs by having slightly larger denticles of serrulae. Males distinguishable from other species by their distinctive penis valves.

Genetic data.

COI. Based on 11 specimens, maximum within species distance is 1.75% and the nearest neighbours, diverging by a minimum of 0%, are Euura brevivalvis , Euura glutinosae , and Euura viridis . BINs: BOLD:AEC8057, BOLD:ABZ5797, BOLD:ACF5540 (main cluster).

Nuclear. Based on 6 specimens, maximum within species distance is 0.25% (0.15% based on haplotypes of individual females). The nearest neighbours, diverging by a minimum of 0.63%, are Euura brevivalvis and Euura glutinosae .

Host plants and behaviour.

Hosts: Betula pendula ( Kangas 1985) and B. pubescens ( Kontuniemi 1960). Probably two generations per year, of which larvae identified as Pteronidea pseudodispar belong to the second generation ( Lindqvist 1969).

Distribution.

Palaearctic ( Taeger et al. 2006; Sundukov 2017). Specimens studied are from Finland, Germany, Italy, Portugal, Sweden, and United Kingdom.

Type material.

Pteronidea pseudodispar Lindqvist, 1969. HT, ♀, http://id.luomus.fi/GL.3514, MZH.

Figures

Fig ure 4. Euura dispar DEI-GISHym 83956, female, photographed shortly after killing in a freezer.

Figure 8. Lancets of Euura bergmanni group. A Euura dispar DEI-GISHym 84146 B Euura viridis DEI-GISHym 21364 C Euura glutinosae DEI-GISHym 80498 D Euura brevivalvis DEI-GISHym 31135.

Figure 11. Penis valves of Euura bergmanni group. A Euura bergmanni ZMUO. 032583 B Euura dispar DEI-GISHym 88519 C Euura viridis ZMUO. 030834 D Euura brevivalvis DEI-GISHym 84227 E Euura brevivalvis ZMUO. 030870 F Euura sylvestris DEI-GISHym 83594 G Euura sylvestris ZMUO. 033416 H Euura glutinosae DEI-GISHym 84096 I Euura leptocephalus DEI-GISHym 88730 J Euura respondens DEI-GISHym 12514.

Figure 15. Euura dispar adults. Female ZMUO. 034987 (A, B), male ZMUO. 040517 (C, D). Identification of the female is uncertain.

Figure 24. Euura glutinosae (A, B) and possible Euura dispar (C-E) larvae A, B France 2007 Alnus glutinosa (photos: Henri Savina) C Pyrenees 2010 Betula (photo: Henri Savina) D Finland 2020 swept larva E DEI-GISHym 12579 Germany 2020 Betula pendula. The larvae with paired red dots (C, D) have earlier been considered as representing Pteronidea pseudodispar that we consider synonymous to Euura dispar, but whether this type of larvae truly represent Euura dispar remains unconfirmed.