Clouded Apollos inhabit meadows and woodland clearings with plenty of flowering plants, both in the lowlands and in the mountains. It is not usually found at altitudes above 1500 m except in the Central Asian mountains where it is also seen at higher altitudes.
   They lives mainly in pastureland.
   The eggs hatch in April, and the delicate larvae must immediately find the only food they can eat: the leaves of corydalis, one of our first spring flowers.
   The larvae quickly eat their fill and pupate a month later.
   At the start of June, the fully formed white clouded Apollo butterflies hatch. They search for nectar in flowers of many different species including dandelion, sticky catchfly, cow parsley and meadow buttercup.
   The butterflies begin mating and the females then lay eggs of 1 mm to 2 mm seemingly at random on dry leaves and in dry grass.
   The eggs rest for ten months until April the following year, when they hatch. (The Clouded Apollo lives almost its whole life in egg form.)   
   Parnassius mnemosyne is a white butterfly with black marked wings with black veins and translucent wing tips. The ventral surface is similar.    The body has white hairs and the antennae are completely black.
   They were once found in many southern Swedish landscapes, but today survive only in small populations in Uppland, Blekinge and Ångermanland.
   They are classified as endangered (EN) on the Swedish red list.
   Pastures and woodland becoming overgrown is the principal reason for the clouded Apollo’s decline. Corydalis is still found in many parts of southern Sweden, but no longer in the abundant quantities required to sustain healthy numbers of Clouded Apollos. They also needs plenty of nectar plants in the vicinity.
    The species was named in the classical tradition for Mnemosyne the mother of the nine Muses.