Reinstatement and revision of the genus Adelmeria(Zingiberaceae) endemic to the Philippines

In 1909, Ridley published Adelmeriacharacterized by its congested terminal inflorescence with large persistent floral bracts. All five species at some point placed in Adelmeriawere synonymized in Alpiniaby Loesener and subsequent authors. Several phylogenetic studies revealed that Alpiniais highly polyphyletic, suggesting that it should be split into several genera. In the present study, we sampled all five species initially placed in Adelmeriaplus additional ones with a similar morphology. The combined analysis of the ITS and trnK/matKregions showed that these species formed a strongly supported monophyletic group inside the Alpinia eubracteaclade of the tribe Alpinieae. Although not completely diagnostic, the following morphological characters separate Adelmeriafrom most of the species currently inside the Alpinia eubracteaclade: bilobed ligules; congested inflorescences; utricular bracteoles; sessile flowers; crestless anthers; obovoid fruits. Considering this molecular and morphological evidence, the recognition of Adelmeriais highly justified. In this present paper, we reinstate the genus which is endemic to the Philippines and provide a comprehensive taxonomic revision including a discussion of the application of the name Elmeria. A key to nine species of Adelmeria, four of which (A. dicranochila, A. isarogensis, A. leonardoi, A. undulata) are new to science, is provided as well as full descriptions and preliminary conservation assessments. Interestingly, monoecy was observed in A. oblongaand reported for the first time for Adelmeria. Four lectotypes and one epitype are designated in this study.