Identification of Oberonia (Orchidaceae) on Kozushima Island, Japan

抄録

To clarify whether Oberonia from the Izu Islands are O. japonica or O. makinoi, molecular and morphological analyses of Oberonia from Kozushima Island were performed. Data derived from the nuclear rDNA internal transcribed spacer regions, plastid matK with a trnK region, and single-nucleotide polymorphisms from MIG-seq showed that Oberonia from Kozushima Island belonged to O. japonica. The Kozushima plants flowered from May to June, similar to O. japonica, but their leaves were wider than those of O. japonica. Most herbarium Oberonia specimens from the Izu Islands had wide leaves similar to those of the Kozushima plants, although some had narrow leaves and were indistinguishable from O. japonica. We suggest that the plants from the Izu Islands belong to O. japonica. Further analyses are necessary to clarify whether the plants from the Izu Islands should be treated as an intraspecific taxon or an intraspecific variation.