Melitaea deione (Geyer, 1832)

Host plants:
The caterpillars live in Valais mostly on Linaria angustissima (e.g. egg observations in July 2008), according to literature also on Linaria vulgaris and rarely (secondary?) on Digitalis. In Andalusia (Sierra Nevada), I met eggs only at Digitalis obscura. The butterflies were only present where the plant occurred. Digitalis obscura has a similar quality of the leaf as Linaria and there is likely to be the main host plant.

Habitat:
Melitaea deione inhabits hot, shrub-rich slopes, embankments and bushy, often rocky grasslands, especially in the south also forest edges and scrub.

Life cycle:
The eggs are deposited in batches on leaf undersides. The caterpillar overwinters half-grown. The adults fly in a single generation mostly in June and July. Less commonly, there is also a partial second generation. This is evidently more frequent in the Valais than in Andalusia!

Endangerment factors:
In Valais already many populations have been extirpated through the expansion of vineyards, others by reforestation and bush encroachment. Overall, the main threat is the increasingly intensive (agricultural) overuse of the countryside, next to the housing development (settlements, infrastructure).

Remarks:
The Atlanto-Mediterranean distribution stretches from Morocco across the mountains of the Iberian Peninsula and Southern France to Northern Italy and Switzerland (Valais, subspecies berisalii).