Host plants:
The host plant is usually Coronilla varia, the ssp. elegans, however, feeds especially on Coronilla coronata. In Greece, the species lives on Coronilla varia (Olympus), and most likely also Hippocrepis comosa that prevailed at a moth observation site (Pangeon) and was accepted by the larvae in breeding easily.
Habitat:
Zygaena angelicae colonizes edges in calcareous grasslands and heathland. The ssp. elegans only occurs in dry and partial sunny, small grassland-like edges in open woodland (mostly beech at suboptimal, shallow soils at dry, steep slopes). In Greece it settles also in edges in Alpine pastures, so up to 2000m above sea level at Mount Olympus. In Southeastern Europe Zygaena angelicae seems to prefer mountainous regions between 1000 and 2100m elevation.
Life cycle:
Larvae of the ssp. elegans are mature early in the season, so in hot years in early May, otherwise more from mid-May to early June. The moths fly from June to July (only rarely still in early August). Other subspecies are on the wing a little later between July and early August. This species is characterized as all Zygaena by potential multiple hibernation in the larval stage.
Endangerment: strongly endangered
Endangerment factors:
The ssp. elegans has declined significantly and still occurs only in a few, small habitats that are partly probably forest-free by nature (Hofmann in Ebert 1994). The decline happened due to dense and dark afforestations, intense mowing of road side verges (at secondary sites in beech forests) and probably by changed conditions of succession (nitrogen deposition!). Today many of the remaining habitats are subject of maintenance measures in order to prevent further decline.
Otherwise, Zygaena angelicae is threatened by loss of suitable grasslands (bush encroachment, pine reforestation, overbuilding).
In the mountains of Southeastern Europe the endangerment is less severe (almost only locally through ski tourism and its infrastructure, and at presumably more locations by overgrazing).
Remarks:
In Germany Zygaena angelicae is nowadays probably only found in northern Bavaria and Thuringia, maybe also Saxony. The ssp. elegans (formerly even sometimes regarded as a separate species) is still found in very few places in the (mostly western) Swabian Alb in southwest Germany, Baden-Württemberg.
Overall, Zygaena angelicae shows a widespread Ponto-Mediterranean distribution pattern (from Germany across Eastern and Southeastern Europe to the Ukraine).