Integrative delimitation of Apolygus (Insecta: Heteroptera: Miridae: Mirinae) species known from Russia with the emphasis on Apolygus lucorum and Apolygus spinolae having trans-Palearctic distribution

Apolygus (Insecta: Heteroptera: Miridae: Mirinae) is a large and taxonomically challenging trans-Palearctic genus comprising 74 species, and it has never been revised. The greatest diversity of this genus occurs in Asia, and 15 species have been recorded from Russia. Among them, Apolygus limbatus, Apolygus lucorum, and Apolygus spinolae are trans-Palearctic, and A. lucorum and A. spinolae are economically important as pests.

Previous studies have shown that A. lucorum and A. spinolae are very similar in morphology and that the barcoding region might not be suitable for their identification. In this study a revision of the Apolygus representatives inhabiting Russia is provided based on morphological and molecular data. Mitochondrial (COI and 16 S rRNA) and nuclear markers (ITS 1 and 28 S 3 rRNA) were used for phylogenetic analyses and automatic species delimitation methods were applied.

Apolygus lucorum, A. malaisei, A. nigronasutus, A. nigrovirens were treated as junior synonyms of A. spinolae because morphological and molecular data did not show differences between those species. Apolygus shikotan sp. nov. was described as new to science. Morphological data and the COI phylogeny show that A. limbatus might represent two separate species.

However, additional specimens and nuclear markers for both groups are needed to test this hypothesis. The synonymy of A. syringae with A. hilaris was supported based on the morphological data. Apolygus gotorum and A. subhilaris are reported from Russia for the first time.

The nuclear marker ITS 1 is the most reliable marker for species delimitation and identification of Apolygus species.