Ametastegia pallipes (Spinola, 1808)

Material examined.

Greenland. Narsarsuaq • 1 ♀ (SDEI; DEI-GISHym 81441), 20 June 2025, Liston leg. • 1 ♀ (TUZ; TUZ 399063), 1 ex ovo larva from preceding female (TUZ; TUZ 399075), 23 June 2025, Prous leg. Qassiarsuk • 4 ♀♀ (SDEI), 21 June 2025, Liston leg. • 1 ♀ (TUZ; TUZ 399056), 21 June 2025, Prous leg. • 1 ♀ (TUZ; TUZ 109608), 21 June 2025, Liston leg. • 5 ♀♀ (OLC), 21 June 2025, Lønnve leg.

Habitus and variability

(Fig. 1). No significant differences observed. Length 6–7 mm. The legs of all specimens are very dark: metafemur nearly entirely black, and only basal half of metatibia white.

Habitats.

The Narsarsuaq specimens were swept in an area between houses, where some patches of Viola tricolor L. occur. This Viola species is not indigenous to Greenland (Rune 2011). Most of the Qassiarsuk specimens were swept near a stream where one or more native Viola species grow, but not V. tricolor, and the other specimens were from drier pasture and meadows on slopes where flowering Viola, probably V. canina L., was noted.

Host plants and biology.

In Europe, several species of Viola have been recorded as hosts (Chawner and Peacock 1923; Lacourt 2001). One female from Narsarsuaq was induced by MP to lay eggs in Viola tricolor, of which two hatched, but only one larva (Fig. 1) was reared to the prepupal stage and then stored in alcohol (the other was accidentally lost). At least three annual generations have been observed in England (Chawner and Peacock 1923). Ametastegia pallipes is thought to be entirely parthenogenetic, with no male specimens known.

Distribution.

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

Remarks.

This is probably the sawfly species recorded by Vilhelmsen (2015) as Ametastegia sp.: “ Only known from a few larvae collected in Upernaviarsuk and Narsarsuaq ”.

Genetics.

The COI of the single sequenced specimen (TUZ 399056) is one nucleotide different (0.15 %) from the main widespread variant (several countries in Europe and Canada) of Ametastegia pallipes.