Reexamination of the primrose on the Shimokita Peninsula, northernmost Honshu, Japan, which has been treated as Primula modesta Bisset & Moore showed that it is closely related to P. sorachiana Miyabe & Tatew., endemic to Hokkaido, based on morphology and phylogenetic investigations. However, it can be distinguished from P. sorachiana by its smaller stature, flowering scape shorter than leaves, base of bracts non-saccate, larger and fewer flowers, and shallowly parted calyx lobes. Based on the results, the plants from the Shimokita Peninsula are described as a new species, P. shimokitana Mas. Yamam.

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Murdannia (Commelinaceae), consisting of some 60 species, is unusual in the family in having both actinomorphic and zygomorphic flowers usually with the median petal on adaxial side, and having either two or three antisepalous stamens. To understand floral evolution in the genus in light of a phylogenetic context, we conducted phylogenetic analyses of 18 species and one cultivar mainly from Asia using plastid DNA sequences, then examined their respective floral morphology. The results showed a monophyly of all 16 Asian species of Murdannia and one cultivar, and of the ten species with zygomorphic flowers. Comparisons with flowers of related genera suggest that great morphological changes occurred early in the evolution of Murdannia, including rotation of a symmetrical plane by 60 degrees so that the median petal of the flowers is positioned at the top on the adaxial side. Within the genus, a change in floral symmetry from actinomorphy to zygomorphy occurred one time and was accompanied by androecial zygomorphy resulting from replacement of one of three antisepalous stamens by a staminode. Additionally, the two latero-abaxial petals usually spread laterally around 160–180 degrees. The infrageneric classification of the Asian species is also briefly discussed.

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In the oceanic Bonin Islands, both the flora and fauna exhibit adaptive radiation and ecological differentiation. Elaeocarpus photiniifolia Hook. & Arn. (Elaeocarpaceae), a tree endemic in the Bonin Islands, grows in a wide range of environments, from dry scrub to mesic forests. In the Chichijima Islands, we observed genetic differentiation between the shrub ecotype in dry scrub and the tree ecotype in mesic forests. Conversely, on Hahajima Island, only one genetic group was known in mesic forests. Recent surveys, however, revealed a small number of individuals of E. photiniifolia in the dry scrub of the Hahajima Islands. This study aimed to determine whether genetic differentiation corresponding to vegetation types also occurs in the Hahajima Islands. To investigate this, we used 17 EST-SSR markers for genotyping to determine the genetic attributes of individuals in the dry scrub of the Hahajima Islands. Our data revealed that individuals from the dry scrub were highly differentiated genetically from the known genetic group of Hahajima Island that occurs in mesic forests. Additionally, we observed that individuals in the dry scrub flowered earlier than those in mesic forests. Our findings indicate that E. photiniifolia is both genetically and ecologically differentiated in the Hahajima Islands, with the dry scrub populations likely having originated from a secondary migration of shrub ecotypes from the Chichijima Islands, possibly facilitated by infrequent seed dispersal across island groups.

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Phylogenetic analyses based on SNPs data detected by MIG-seq was used to reappraise the intraspecific taxonomy of Cassytha filiformis (Lauraceae) in Japan and Taiwan. The network analysis distinguished two terminal clades, one comprising plants with glabrous stems and another comprising plants with pubescent stems. The network analysis also revealed a genetically intermediate clade comprising plants with glabrous and pubescent stems. STRUCTURE analysis revealed the intermediate plants to be of hybrid origin for the first time between the two terminal clades of Cassytha. ML analysis excluding the hybrid plants revealed two clades: one morphologically identifiable as C. filiformis var. filiformis and another identifiable as C. filiformis var. duripraticola based on hairs on the stems following the taxonomic concept of Hatusima (1976).

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Based on morphology as well as on karyotype and MIG-seq analyses, two new hybrids, Polygonatum ×hizenense and P. ×sefuriense, from Mt. Sefuri, Pref. Saga, Japan, are described. Polygonatum ×hizenense has 26–29% pollen stainability and 2n = 20, is morphologically intermediate between P. falcatum (with 78–98% pollen stainability and 2n = 18) and P. macranthum (with 95–100% pollen stainability and 2n = 22), which occur parapatrically on Mt. Sefuri. A Neighbor Net network based on MIG-seq data showed P. ×hizenense to be positioned between the P. falcatum cluster and the P. inflatum-P. macranthum cluster, also indicating it to be of hybrid origin between P. falcatum and P. macranthum. Likewise, P. ×sefuriense has 29–37% pollen stainability and 2n = 19, morphology intermediate between P. amabile (with 74–92% pollen stainability and 2n = 20) and P. falcatum, which also occur parapatrically on Mt. Sefuri. The MIG-seq analysis showed P. ×sefuriense to be positioned between the P. falcatum cluster and the P. amabile-P. lasianthum var. lasianthum cluster in the obtained network, indicating it to be of hybrid between P. amabile and P. falcatum. In addition, our analysis based on MIG-seq suggested that P. lasianthum var. coreanum should be separated from var. lasianthum as a distinct species, P. taquetii.

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A simple leaf form of Gamblea innovans, f. simplicifolia (Araliaceae), is described. It is distinguished from f. innovans in predominantly having simple leaves with a cordate base. It was found in two disjunct localities, in Kinki and Tohoku districts, Honshu, Japan.

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Asterella khasyana (Griff.) Grolle is reported new to Vietnam based on morphology and a phylogenetic analysis of specimens collected in Vietnam. Illustrations, ecological information, and taxonomic notes based on the Vietnamese materials are provided. A key to four species of Asterella known from Vietnam is also included.

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