A contribution to the knowledge of the Arctic forms of the genus Chrysomela L. (Coleoptera, Chrysomelidae)

Detailed morphological (including description of the larva) and ecological characteristics of the leaf beetle Chrysomela wrangeliana L. Medvedev, endemic to Wrangel Island (the Chukchi Sea), are given. The annual life cycle of the species is similar to that of Ch. collaris L., with hibernation at the larval stage. In nature, Ch. wrangeliana develops on Salix glauca, a prostrate willow species, the larval development taking 20-25 days at the mean air temperature of about 6°C. The distribution pattern of Ch. wrangeliana on Wrangel Island is discussed, and a sharp increase in its abundance following a series of warm seasons is recorded. The ranges of Arctic species of the subgenus Pachylina L. Medvedev are separated from that of the nominotypical subspecies of Ch. collaris by a wide disjunction in the Subarctic regions of Siberia. The taxonomy of the subgenus Pachylina is reconsidered, with a new subspecies Ch. collaris hyperborea L. Medvedev subsp. n. being described from North Yakutia and continental tundra of the Chukchi Autonomous Area. Chrysomela wrangeliana L. Medvedev and Ch. taimyrensis L. Medvedev are regarded as distinct species, rather than subspecies of Ch. blaisdelli. © 2011 Pleiades Publishing, Ltd.