The caterpillars of the Southern Festoon live on various birthworts, such as Aristolochia clematitis, Aristolochia rotunda, Aristolochia pallida and Aristolochia pistolochia. Because their foodplants grow in different habitats and the caterpillars also have different foodplants in different areas, this spring butterfly can be found in quite different habitats. In the western part of its range, it can be seen in open places along rivers with the foodplant Aristolochia rotunda. In the mountains, the butterflies can be seen in dry, sunny, rocky places, where Aristolochia pallida and Aristolochia pistolochia grow. In the Pannonian region, the species is found on sites with ruderal vegetation, e.g. along the Danube, but also in vineyards on sunny slopes, where Aristolochia clematitis grows as a weed. In Greece, the butterfly occurs in damp areas, as well as on dry slopes, according to the species of birthwort used as foodplant. The eggs are laid singly or in small groups on the underside of the leaves, where the caterpillars are usually also found. The caterpillars have a striking appearance. Mostly beige with black spots, they have some orange tubercles on each segment, each ending in a black, spiny tuft. The Southern Festoon has one generation a year and hibernates as pupa. Habitats: dry calcareous grasslands and steppes (14%), humid grasslands and tall herb communities (12%), mesophile grasslands (12%), heath and scrub (9%), dry siliceous grasslands (7%), sclerophyllous scrub (7%), alluvial and very wet forests and brush (7%).
