The Lepidoptera are among the most successful groups of insects. They are found on all continents, except Antarctica, and inhabit all terrestrial habitats ranging from desert to rainforest, from lowland grasslands to mountain plateaus, but almost always associated with higher plants, especially angiosperms (flowering plants). Among the most northern dwelling species of butterflies and moths is the Arctic Apollo ("Parnassius arcticus"), which is found in the Arctic Circle in northeastern Yakutia, at an altitude of above sea level. In the Himalayas, various Apollo species such as "Parnassius epaphus" have been recorded to occur up to an altitude of above sea level.