Boloria selene (Denis & Schiffermüller, 1775)

Host plants:
The larva feeds on Viola secies such as Viola canina or Viola palustris.

Habitat:
Boloria selene inhabits forests (clear-cuttings), fens, bog edges and usually acidic grasslands. In the Swabian Jura Boloria selene occurs more in coniferous afforestations, on clearings and humid grasslands. It is usually missing in xerothermic calcareous grasslands.
Boloria selene often still occurs in heavily overgrown (grasses, herbs, bushes) clearings where Boloria euphrosyne has already vanished.

Life cycle:
The adults fly in two generations from May to early July and from August to September. The last generation is often only partially. At suitable sites (especially wet clearings) they are usually quite abundant.

The caterpillars overwinter probably as L3.

Endangerment: endangered

Endangerment factors:
In the lowlands Boloria selene is in decline in many regions due to habitat loss because of eutrophication and destruction of wetlands and a tendency in forestry towards darker and darker woodlands (high forests without clearings and any open places). Fen sites were pushed back in many regions mainly by the intensive agriculture and forestry to very small remains.

Remarks:
The distribution is Holarctic. In Europe it is more restricted to the central and northern areas (misses in the direct Mediterranean region).