Erynnis tages (Linnaeus, 1758)

Host plants:
The larva feeds on Fabaceae, especially Hippocrepis comosa, Coronilla varia and Lotus corniculatus.

Habitat:
Suitable as habitat are especially nutrient-poor, warm grasslands of all kinds (especially on limestone), sparsely vegetated clearcuts, very broad, meagre road embankments and similar locations.

Life cycle:
Usually, this species formed only one generation in Central Europe, that appeared from April to early July, in the Alps later. In the lowlands regularly a partial second generation is observed (July/August), in medium high altitudes only in hot summers (e.g. 2003). Nowadays the second generation is more regular even on the Swabian Alb (and other low mountain ranges). In the lowlands this second generation is common now and sometimes even a partial third generation appears (then adults between April and June, July and August and in September/early October).

The caterpillar lives in a webbed shelter (leaf case) on the host plant as it is usual for Pyrginae and is - in case of one generation - fully-grown mostly in August, but pupates only after hibernation in March or April. It is questionable if also larvae of late ovipositions (August/September) reach this last instar prior to winter. Thus they may hibernate also in younger instars as it is the case in C. alceae. But this is not yet documented in the field.

Endangerment factors:
In the mountains and in the south Erynnis tages is threatened only little. Otherwise this species is in strong decline in Central Europe (especially in areas with nowadays only small calcareous grasslands). It benefits a bit from global warming.

Remarks:
The butterfly is distributed in most of Europe (except in the far north) and Asia to the Amur.