First Evidence of Presence of Varroa underwoodi Mites on Native Apis cerana Colonies in Primorsky Territory of Russia Based on COX1 Gene.

The species of genus Varroa mites parasitize on the honey bees of genus Apis. Unlike the well-studied V. destructor and V. jacobsoni mites, V. underwoodi remain less known. According to English language publications, the proven V. underwoodi distribution area of A. cerana colonies covers Nepal, South Korea, Indonesia, Papua New Guinea, Vietnam and China, but not Russia even though it had been described morphometrically in Russian language publications in Russia's Primorsky Territory. According to Vavilov's law (1920) of a homologous series, all the species of V. underwoodi, V. destructor and V. jacobsoni have the ability to spill over onto new hosts. Thus, V. underwoodi is a potential parasite of A. mellifera that should be carefully studied. In this study, V. underwoodi mites in colonies of honey bee subspecies A. c. ussuriensis native to Russia's Primorsky Territory are first proven using both morphometry and mitochondrial COX1 gene sequencing. The genetic divergence and p-distances between V. underwoodi and other Varroa species ranged from 7 to 10% and from 0.072 to 0.099, respectively, which matched the intraspecific level of differences. Two identical northernmost V. underwoodi samples from Russia's Primorsky Territory and China's Jilin province with GenBank accession number MH205176 were assigned as COX1 haplotype China 1 MH205176. The first discovery of V. underwoodi in the Primorsky Territory in northern Asia outlined the northern border of its range. [ABSTRACT FROM AUTHOR]