Polymorphism of the harlequin ladybird Harmonia axyridis (Coleoptera, Coccinellidae) Baikal population

Abstract

The phenotypic composition of the Baikal population of the harlequin ladybird Harmonia axyridis (Pallas, 1773) was analyzed based on the material collected in Irkutsk Province in 2009–2010. Significant microgeographic phenotypic variation was revealed on the Baikal coast and in the city of Irkutsk. The morph axyridis, widespread in Siberia, was dominant (80–90%) but the light-colored morph succinea was also present with high frequencies (43–59%) in some samples. Some individuals possessed an elytral ridge, their frequency in the Baikal population being low (4–6%). An increase in the number of the morph succinea in Irkutsk Province is not related to hybridization between the populations from the Far East and Siberia.