Phylogenetic and conservation status of the endangered terrestrial orchid Nervilia nipponica (Orchidaceae) in Korea

Abstract

The putative Japanese endemic Nervilia nipponica was discovered recently on Jeju Island in Korea. However, Japanese populations of N. nipponica have since been shown to comprise two polyphyletic taxa. To confirm the taxonomic status of the Korean Nervilia populations, we compared ITS1, matK and trnL intron sequence data with that from the two cryptic Japanese taxa. Our results confirmed all Korean populations as belonging to the true N. nipponica s.s, which must shed its endemic status. Korean accessions showed no distinct genotypic patterning, with samples from all populations and representing two distinct colour forms forming a single monophyletic clade. The extremely low level of genetic diversity detected within N. nipponica on Jeju Island underscores the urgent need for measures to secure the species from local extirpation. We conclude that N. nipponica is a priority for conservation and recommend that systematic controls and sustained efforts are required to ensure its protection. © 2011 Elsevier Ltd.