Genome-wide SNP data reveal phylogenetic relationships and further new species of lace bugs (Hemiptera, Heteroptera, Tingidae) endemic to the Japanese oceanic islands (the Ogasawara Islands), providing insight into their speciation.

The Ogasawara Islands of Japan are oceanic islands that are home to two endemic genera of lace bugs (Hemiptera, Heteroptera, Tingidae), namely, Acanthomoplax Souma & Kamitani, 2021 (Tinginae, Tingini) and Omoplax Horváth, 1912 (Tinginae, Tingini). In the present study, phylogenetic analysis, using genome-wide single-nucleotide polymorphism (SNP) data from multiplexed inter-simple sequence repeat (ISSR) genotyping by sequencing (MIG-seq), is conducted for the genus Omoplax, which is hypothesized to have undergone adaptive radiation in the Ogasawara Islands. Additionally, population genetic analysis using these data is conducted for O. desecta, for which two host races are known. Combining the results of these analyses with the morphological differences, O. sandoru Souma, sp. nov., previously identified as the population in Hahajima Group of O. desecta, is described as a new species. In conclusion, the following nine lace bug species are recognized in the Ogasawara Islands: A. tomokunii Souma & Kamitani, 2021, O. desecta (Horváth, 1912), O. hisasuei Souma, 2025, O. inugusu Souma, 2025, O. karubei Souma, 2022, O. kobugashi Souma, 2025, O. majorcarinae Guilbert, 2001, O. mukojimensis Souma, 2022, and O. sandoru Souma, sp. nov. An updated key for identifying all nine species of lace bugs occurring in the Ogasawara Islands is provided. Finally, insights into phylogenetic relationships and the mechanism of speciation within the genus Omoplax are discussed.