This study reports sterile triploid and sexual tetraploid of L. grammitoides from Japan based on chromosome counts, spore morphology, and ploidy analysis.
While four species of Liriope, L. minor, L. muscari, L. spicata and L. tawadae, are recognized in Japan, at least two of them are known to have tetraploids and hexaploids in the same species and are likely to be reproductively isolated. To reconfirm recognition of those species, we conducted analyses of morphological characters as well as of ploidy levels, in addition to phylogenetic analysis of chloroplast DNA and genome-wide single nucleotide polymorphism analysis of nuclear DNA (MIG-seq), using 117 individuals from 99 populations. Consequently, the following six genetic clusters were obtained: (1) diploid L. minor, (2) tetraploid L. spicata from Honshu-Kyushu, (3) tetraploids of L. muscari and L. spicata, both from South Ryukyu, (4) hexaploid L. muscari from Honshu-Kyushu, (5) hexaploids of L. muscari, L. spicata (one population) and L. tawadae, all from central Ryukyu, and (6) hexaploid L. muscari from Miyako Isls. Based on a totality of the evidences, six species corresponding to the six genetic clusters: L. minor, L. fauriei (comb. nov.), L. stolonifera (sp. nov.), L. exiliflora, L. tawadae, and L. littoralis (sp. nov.) are recognized. A diagnostic key to the six species, as well as descriptions of the two new species, are provided.
Three species of Acanthaceae, Barleria siamensis, Staurogyne racemosa and Thunbergia geoffrayi, collected on the Bolaven Plateau, southern Laos, are reported in the flora of Laos for the first time. The voucher specimens, distribution, habitat and ecological information, vernacular names, photographs, and taxonomic notes are provided for each species. In addition, lectotypes are proposed for Staurogyne racemosa and Thunbergia geoffrayi.
A new species of Homalomena (Araceae), H. wayang, is described from Palembang, South Sumatra, Indonesia. Molecular analysis based on ITS sequence places H. wayang in close relationship with H. sumatrensis, with a sequence similarity of 94.5%. Although genetically allied, the two species are clearly distinct morphologically based on several important characteristics of reproductive organs, supporting the recognition of H. wayang as a separate taxon. The discovery of this species adds to the of Homalomena in Sumatra.
Yakushima is an island known as a biodiversity hotspot for vascular plants in the Japanese Archipelago. At high-elevation areas of Yakushima, three miniaturized groups of Hypericum sect. Hypericum (Hypericaceae) are known. They are distinguished by gland characteristics of the leaf lamina: Group I having only pellucid glands, Group II with both pellucid and dark glands, and Group III with only dark glands. To further distinguish these three groups, we analyzed the phylogenetics, population genetics, morphology and flow cytometry. Genetic analyses showed that Groups I and III are not closely related and clearly differentiated. In addition, individuals of Group II showed intermediate genetic and morphological characteristics of the other two groups. The three groups also differ in ploidy levels; Groups I, II, and III are tetraploid, triploid, and diploid, respectively. These findings suggest that Groups I and III represent two distinct species that may have independently evolved into miniaturized forms on Yakushima, while Group II represents their F1 hybrids. Based on this evidence, we describe Group III as a new species, H. yaedakense D.Takah. & Yahara, and propose a new combination, H. kiusianum Koidz. var. lucidum (Y.Kimura) D.Takah., for Group I.
