Can be similar to Light Crimson Underwing, but is usually larger with a darker and less variegated forewing. The shape of the black band on the hindwing is characteristic, although this can be hard to see on live examples.

Overwinters as an egg. The caterpillar feeds from April to early June.

Size and Family

  • Family: Underwings
  • Large Sized 
  • Wing Span Range (male to female) - 58-74mm

Conservation status

  • UK BAP: Priority Species
  • Red Data Book

Caterpillar Food Plants

Pedunculate Oak (Quercus robur) and possibly Sessile Oak (Q. petraea)

Habitat

Oak woodland.

Distribution

  • Countries – England
  • New Forest, but also found very locally in Wiltshire. Formerly also Kent, probably Sussex and possibly elsewhere. Occasionally recorded elsewhere as an immigrant.
  • Distribution Trend Since 1970s = Britain: Stable
Dark Crimson Underwing - Ryszard Szczygieł

Dark Crimson Underwing

Dark Crimson Underwing - Vlad Proklov

Dark Crimson Underwing

Dark Crimson Underwing - Stuart Read

Dark Crimson Underwing

Dark Crimson Underwing - Stuart Read

Dark Crimson Underwing