| Family | Hesperiidae |
|---|---|
| Subfamily | Pyrginae |
| Genus | Spialia |
| Species | sertorius |
| Authority | (Hoffmansegg, 1804) |
| English Name | Red-underwing Skipper |
| European Red List 2010 | Least Concern (LC) |
|---|---|
| EU 27 Red List 2010 | Least Concern (LC) |
| European Red List 2025 | Least Concern (LC) |
| EU 27 Red List 2025 | Least Concern (LC) |
| Habitats Directive | |
| Bern Convention | |
| CITES |
The Red-underwing Skipper is a small butterfly that likes warm habitats. It occurs on calcareous and other dry grasslands, and also in dry, rough vegetation, as long as its larval foodplant, Salad Burnet (Sanguisorba minor), is present. The eggs are laid between the buds on the flowerheads of this plant and the caterpillars feed on the young leaves. Hibernation takes place as a caterpillar, in warm areas when still small, and further north when fully grown. The caterpillars pupate in the litter layer, in a sturdy cocoon made from plant remains. Because of its rapid flight and unremarkable behaviour, this small butterfly is often not even noticed. However, they are often present in large numbers over quite a small area. The butterflies like visiting flowers. It has one or two broods a year, depending on the position of the breeding ground within the range.
Andorra / Austria / Belgium / Belgium: Flanders (Regionally Extinct) / Belgium: Wallonia / Bosnia and Herzegovina (Possibly Present) / Croatia / Czechia / France / France: Mainland / Germany / Hungary / Italy / Italy: Mainland / Italy: Sicily / Liechtenstein / Luxembourg / Netherlands (Regionally Extinct) / Poland / Portugal / Portugal: Mainland / Slovakia / Slovenia / Spain / Spain: Mainland / Switzerland / United Kingdom: Gibraltar /