The larva feeds on grasses, especially Brachypodium pinnatum.
Thymelicus acteon needs xerothermic, but often mild to moderate dense and higher growing grasslands in the lower mountain ranges (e.g. Jura). Best is a mosaic of gappy or stony, low growing parts with loosely and single brachypodium pinnatum and the higher growing edges with denser Brachypodium facies in limestone regions. Thymelicus acteon is missing in the northern Alps.
Thymelicus acteon hibernates in the first instar in a cocoon. The caterpillars are mature in May and June and can be easily found where Brachypodium pinnatum grows on more gappy ground and partly also in denser vegetated areas on the same square with those of Thymelicus lineola and Thymelicus sylvestris (observations on the Swabian Alb in Germany). The adults fly from late June or July to early September.
As species with a narrow ecological licence and a distinct restriction to nutrient-poor, extensively managed grasslands, Thymelicus acteon is endangered and in strong decline in many, especially northern regions.
The distribution extends from the Canary Islands (subspecies christi, partly regarded as a separate species, see in this taxon) across Northwest Africa and Central and Southern Europe to Western Asia.