Host plants:
The caterpillars live on Dorycnium species. Most commonly they are found on Dorycnium pentaphyllum.
Habitat:
Eurranthis plummistaria inhabits in local populations the scrub, sparse forests with small grasslands clearings, grassland edges, rocky slopes and other sites of the larval host plant from sea level up to 1000m above sea level.
Life cycle:
In Southern France, the moths fly from March to early June, depending on the altitude and spring. I found them frequently in April 2010 in the Massif de la Sainte Baume, the Lac de Sainte Croix and north of Sisteron. In some of the sites I observed also Erebia epistygne. The males patrol during the day in restless flight in the habitats. The females behave inconspicuously and fly within the larval habitats only short distances. They usually sit near the ground or are busy laying eggs.
The eggs are laid on twigs of the larval host plant, or even at straws etc. in their vicinity. The caterpillar lives from late April to late July or early August. I found the fully-grown caterpillar north of Sisteron in mid-July 2010. During the day, they were hiding at the base of Dorycnium pentaphyllum shrubs. The pupa overwinters. According to literature Eurranthis plummistaria has two generations in many parts of their range with additional moths in August and September. The caterpillars should thus be found at least from late August until late October. Presumably, this second generation is only partial and is missing completely at several localities.
Endangerment factors:
Eurranthis plummistaria loses constantly sites due to the conversion of scrub and grasslands in settlements, agricultural fields, dense forests etc. It occurs on the other hand also in some hardly to intensifying and thus quite protected locations. Nevertheless, Eurranthis plummistaria must be considered as endangered.
Remarks:
Eurranthis plummistaria has an Atlanto-Mediterranean distribution: North Africa, the Iberian Peninsula, Southern France, extreme western Italy (Liguria). In the French Alps, the moth is found to the north very local in the Hautes-Alpes (e.g. around Gap).