An unexpected occurrence of Amblyseius swirskii (Athias-Henriot) in La Reunion Island (Acari: Phytoseiidae)

The identity of specimens of phytoseiid mites collected inside greenhouses infested by thrips in La Reunion Island was assessed. As the sampled species belongs to the genus Amblyseius, presently containing 415 species which are notoriously difficult to discriminate, morphological and molecular traits were evaluated. Both morphological and DNA comparisons showed that the collected specimens belong to the species Amblyseius swirskii, a successful biological control agent introduced in the market more than ten years ago in Europe and Northern America. This finding was unexpected, as this species was never reported in this part of the world; an accidental introduction is thus suspected.