Euura obducta (Hartig, 1837)

Material examined.

Greenland. Narsarsuaq • 1 ♀ (SDEI; DEI-GISHym 81440), 15 June 2025, Liston leg. • 1 ♀ (SDEI), 16 June 2025, Liston leg. • 1 larva ex ovo (TUZ; TUZ 399076), 18 June 2025, Prous leg. • 3 ♀♀ (OLC), 18 June 2025, Lønnve leg. • 1 ♀ (OLC), 20 June 2025, Lønnve leg. • 1 ♀ (TUZ; TUZ 109630), 22 June 2025, Lønnve leg. • 1 ♀ (SDEI), 22 June 2025, Liston leg. Qassiarsuk • 3 ♀♀ (SDEI), 21 June 2025, Liston leg. • 1 ♀ (TUZ; TUZ 399055), 21 June 2025, Prous leg. • 2 ♀♀ (OLC), 21 June 2025, Lønnve leg. Nuuk • 1 ♀ (OLC), 26 June 2025, Lønnve leg. • 8 ♀♀ (OLC), 3 July 2025, Lønnve leg. • 4 ♀♀ (SDEI), 3 July 2025, Liston leg. Kapisillit • 1 ♀ (OLC), 27 June 2025, Lønnve leg. • 2 ♀♀ (OLC), 28 June 2025, Lønnve leg. • 1 ♀ (OLC), 29 June 2025, Lønnve leg. • 1 ♀ (OLC), 30 June 2025, Lønnve leg. • 1 ♀ (TUZ; TUZ 109631), 27 June 2025, Lønnve leg. • 2 ♀ (TUZ; TUZ 109632, TUZ 399093), 2 July 2025, Prous leg. • 1 ♀ (SDEI), 28 June 2025, Liston leg. 1 ♀ (SDEI; DEI-GISHym 81284), 28 June 2025, Liston leg. • 4 ♀♀ (SDEI), 30 June 2025, Liston leg.

Habitus and variability (Fig. 9).

Length 4.5–5.5 mm. Metafemur nearly entirely black and forewing stigma mainly blackish (clearly darker than costa) in all specimens, except for DEI-GISHym 81284 with metafemur ventral surface nearly entirely pale, dorsal surface only darkened at tip, and forewing stigma largely pale (little darker than costa).

Habitats.

Specimens were collected mostly from patches of grass containing Calamagrostis canadensis (Michx.) P. Beauvois. A female was offered C. canadensis and Poa nemoralis L. for oviposition but laid eggs only on the latter (a reared larva: Fig. 9).

Host plants and biology.

Various genera of Poaceae, such as Poa L., Elymus L., Phleum L., and Dactylis L., are reliably recorded hosts (Prous et al. 2025). Carex L. is often also listed, but this seems to be based on a single observation by Conde (1934) and would benefit from verification. Males are extremely rare and known only from central Europe. At least two annual broods are possible, under favourable conditions.

Distribution.

Occurs widely in the Holarctic (Sundukov 2017; Goulet and Bennett 2021; Smith 1979) and in Europe from Portugal northwards into the Arctic areas of Fennoscandia (own observations). Also recorded in Iceland (Ólafsson 1991).

Remarks.

One specimen was collected from an inflorescence of Taraxacum sp. (OL).

Genetics.

Two sequenced specimens (TUZ 399055, TUZ 399093) both yielded multiple apparently functional COI variants. The dominant variant (in terms of sequencing output) from TUZ 399055 is identical to a specimen from northern Sweden (specimen SL 81 _ C 8 in BOLD), and the same variant is also found in TUZ 399093 as the second most common variant. The dominant variant from TUZ 399093 is a minimum of 1.8 % different from the other E. obducta sequences (the closest cluster contains specimens from Canada, Europe, and Iceland). The dominant variant of TUZ 399093 is 3.1 % (1078 bp) or 3.6 % (including only 658 bp of the barcoding region) different from the dominant variant of TUZ 399055. The second most common variant from TUZ 399055 is closest to some specimens from Finland and the United Kingdom (minimum of 0.8 % different), which together form the most divergent COI cluster in E. obducta. This divergent E. obducta COI cluster is 3.1–5.2 % different from the others. The additional less common variants from TUZ 399055 (one) and TUZ 399093 (two) are unique sequences diverging by a minimum of 0.6–0.9 % from the others in BOLD.

Based on nuclear genes, two specimens from Greenland are identical but differ by 0.1 % – 0.3 % from three other specimens (two from Finland, one from Germany), depending on the selection of nuclear genes (the three European specimens are identical to each other but based on differing available selections of nuclear genes).