Abstract
We conducted phenological and phylogenetic analyses of the flowering of Illigera luzonensis (C.Presl) Merr. (Hernandiaceae), an endangered species native to Ishigaki Island (Okinawa Prefecture, Japan), Taiwan, and the Philippines. Illigera luzonensis from Ishigaki Island flowers only in the morning. Phenological analysis of the flowering of I. luzonensis in Ishigaki Island revealed that the plants bloom not in summer, as previously reported, but rebloom during spring and fall. Thus, populations of this species from Ishigaki Island and Taiwan differ in their flowering phenology, with the latter populations flowering only in the summer. Further, phylogenetic analyses confirmed that the individual from Ishigaki Island was distant from that in the Philippines. These results suggest that the population of I. luzonensis from Ishigaki Island has a unique lineage unlike the populations distributed in the Philippines and Taiwan.
