Euura amentorum (Förster, 1854)

Material examined.

Greenland. Nuuk • 1 ♀ (OLC; DEI-GISHym 40555), 26 June 2025, Lønnve & Olsen leg. • 3 ♀♀ (OLC; including DEI-GISHym 40556, DEI-GISHym 40559), 3 July 2025, Lønnve & Olsen leg.

Habitus and variability (Fig. 2).

Length 3.5–4.5 mm. Three specimens have pale tegula, distinctly pale rear edge of pronotum, and distinctly pale lower part of face; one specimen is darker, with black tegula, almost black pronotum, and darker lower part of face.

Host plants and biology.

Larvae of all species of the Euura amentorum species group feed within the female catkins of Salix species, into which the females oviposit (Liston et al. 2023). The range of Salix species fed on by E. amentorum is very wide. Salix species present where adults were collected were S. arctophila Cockerell ex A. Heller, S. glauca L., and S. herbacea L., and some plants of all these were flowering. At least three of the specimens were swept from S. glauca, a host recorded for E. amentorum both in Canada (Humble 2006) and in northern Europe (Liston et al. 2023).

Distribution.

Occurs widely in the Holarctic, including Iceland. Confirmed males have been found (only) in Europe but are very rare (Liston et al. 2023). Benson (1962) mentioned one male (North Greenland, 82°N, 31°W, 24. VI. 1949) and two females (East Greenland ca. 76°46'N, VII. 1908; West Greenland, Jakobshavn, ca. 69°N, 28. VI. 1951), but the male may represent Euura cornuta (see below), which also has a penis valve with a long spine.

Genetics.

The COI of two sequenced specimens (DEI-GISHym 40555, 40559) is identical to many Euura amentorum specimens from mainland Europe (Finland, Norway, and France) and a specimen from Iceland. The COI sequences of North American (Canada and USA) specimens are 1.2–2.1 % different from the specimens from Greenland. Sequenced nuclear genes of the Greenlandic specimens are also identical to each other and closest to specimens from Finland and Iceland (minimum difference of 0.1 %). A specimen from the USA is 0.5 % different.