Abstract
Iris speculatrix was described from plants collected in Hong Kong and is accepted to extend through southeastern China. The species is scheduled under the Forestry Regulations and is regarded as endangered (EN) according to the IUCN categories. This enigmatic plant exhibits multiple morphological connections to other congeners, and was classified in contrasting groups such as the "Chinenses" or the "Ensatae" irises. Molecular work placed it as an isolated lineage sister to the beardless/uncrested subgroup of the so-called "Xiphion s.l. clade". In this contribution, we integrate molecular analyses, including the plastid sequence data of I. speculatrix, together with a re-evaluation of morphological, ecological, karyological, chorological and phylogenetic data on the Hong Kong plant, to describe the new genus Portiodora. Three-taxon statement analysis was employed as a primary analytical tool, helping to clarify phylogenetic relationships and support the recognition of Portiodora. Two new combinations are established, and an identification key is presented for the "Iris-flower clade". Relationships to other Chinese taxa often related to P. speculatrix, such as I. grijsii, I. cavaleriei and I. fujianensis are discussed, and their inclusion in Portiodora is not favoured based on the available data. Furthermore, the contribution of taxonomic resolution to biodiversity conservation is discussed.