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The genus Aspidistra has restricted distribution in Southeast Asia, Japan, and China, with more than 160 species. Hayata described three endemic species naturally occurring in Taiwan: Aspidistra attenuata Hayata, A. mushaensis Hayata, and A. daibuensis Hayata, but their descriptions in prologues are incomplete. Based on intensive field surveys, specimen observations, and literature consultations, we reexamine the morphology of these three species and further attempt to determine the diversity of this genus in Taiwan. Therefore, we confirm that there are four species in Taiwan, including one new species, A. longiconnectiva C.T. Lu, K.C. Chuang & J.C. Wang.

Based on our morphological observation, we proposed two new Sedum species in Taiwan. Sedum kwanwuense sp. nov. resembles S. morrisonense. However, it differs from the latter in having flatter and longer leaves, and occurring in different habitat, the former growing on humid, rocky slopes under the forest and the latter living on dry rocky slopes beyond the forest. Sedum taiwanalpinum sp. nov. is similar to S. brachyrinchum, but it can be distinguished from the latter by sepal and leaf morphologies (leaf linear-oblong to linear vs. spathulate to linear-oblong, and sepal unequal to subequal, spreading when blossom vs. unequal in length, erect to oblique when blossom). Our observations were supported by a former phylogenetic study. In this paper, besides providing taxonomic descriptions and line drawings of the two new taxa, we also organize an update key to native and naturalized species in Sedum in Taiwan for aiding the identification.

The Sino-Japanese Floristic Region is highly diverse with respect to temperate plants. However, the reasons for this diversity are poorly understood because most studies have only considered geographic isolation caused by climatic oscillations.Heterotropa(genusAsarum; Aristolochiaceae) diverges here and shows high species diversity in insular systems (63 species) compared to continental areas (25 species).Heterotropashows low dispersal ability with small distribution ranges, implying diversification by geographic events, and high floral diversity, implying pollinator-mediated diversification. To reveal how abiotic and biotic factors have shaped the diversity anomaly ofHeterotropa, we conducted phylogenetic analysis using ddRAD-seq and chloroplast genome datasets including 79 species, estimation of floral trait evolution, and comparison of isolation factors within clades based on distribution range and floral trait analysis. Phylogenetic analysis indicates thatHeterotropaoriginated in mainland China and expanded to the Japanese Archipelago in the Miocene, and the major clades almost correspond to geographic distributions. Floral traits evolved repeatedly in the tip nodes within the clades. Although the major clades include a high proportion of species pairs showing isolation by floral traits, there are no conditional relationships between two isolation factors, indicating that most species pairs with floral trait isolation are distributed allopatrically. The repeated exposure and submergence of land-bridges caused by climatic oscillations would have led to significant population fragmentation in insular systems. Thus, the diversity anomaly ofHeterotropawould have resulted from geographic and climatic events during the Miocene, while subsequent repeated floral trait evolution would have followed geographic isolation during the Pleistocene.

The present paper reports a newly recorded Asarum, A. satsumense F. Maekawa, collected from Taiwan. This species was for merely recorded as an endemic species in Kagoshima, southern Kyushu, Japan. However, recently it was found in northwestern Taiwan, Miaoli and Taichung Counties. Asarum satsumense resembles A. macranthum Hook. f. of Taiwan, but can be distinguished by having a more depressed pyriform perianth tube, larger perianth tube entrance, tessellate-reticulate apically but longitudinally thick-ridged basally inner surface of perianth tube (vs. tessellate throughout the inner wall), and denser supratectate warts on pollen grains. Taxonomic description, line drawing, pollen SEM plates, chromosome number, distribution information, and color photographs of floral characters of this newly recorded species are provided to aid its identification.

Asarum ampulliflorum Lu & Wang, sp. nov. (Aristolochiaceae), collected from Taiwan, is described and illustrated here. Asarum ampulliflorum is similar to A. asaroides (Morr. & Decne.) F. Maekawa in appearance but can be differentiated from the latter by leaf length equal to width (vs. length longer or shorter than width), perianth tube smaller (8.7–11.7 mm × 13.8–18.1 mm vs. 20.0–25.0 mm × 25.0–30.0 mm) and more compressed (ratio of the perianth tube length to the diam. at the widest points of tube 0.62−0.66 vs. 0.80−0.83), and limb lobe nearly as long as perianth tube (vs. shorter than perianth tube). We have compared the species with similar species in Taiwan and east Asia and have provided an artificial taxonomic key for A. ampulliflorum and related species.

BackgroundRecently, we discovered an unknownAsarumfrom Taiwan which is closely related toA. crassisepalumS.F. Huang, T.H. Hsieh and T.C. Huang andA. taipingshanianumS.F. Huang, T.H. Hsieh and T.C. Huang by sharing a thick leaf blade, spreading perianth-lobes and a conical to cylindrical perianth-tube. We compared it with other related species and identified this plant as a new species.ResultsThis new species differs distinctly from the above two related species by having larger plant body, shortened rhizomes and an inner surface of the perianth-tube that is covered with numerous simple trichomes (vs. glandular trichomes). The pollen tectum in this new species is perforate, which differs from the incomplete reticulate with small supratectate granules inA. crassisepalumand the compact rugulate with small supratectate granules inA. taipingshanianum. Furthermore, these three species are geographically separated from one another.ConclusionsAsarum pubitessellatumC.T. Lu & J.C. Wang, a new species is described and illustrated. The trichomes on the inner surface of the perianth-tube and pollen micromorphology were the valuable characters in the low-level classification ofHeterotropaspecies in Taiwan.

Background An unknown Sedum was found from the limestone region in Taiwan. After a detailed comparison with other congeners in Taiwan and neighboring countries, we identified this plant as a new species. Results This new taxon resembles S. nokoense Yamamoto, S. alfredii Hance, and S. uniflorum Hook. & Arn. subsp. oryzifolium (Makino) H. Ohba, but differs in leaf shape, sepal morphology, and seed testa micro-morphology. Ecologically, this new taxon occurs exclusively on limestone, while S. nokoense and S. alfredii grow in non-limestone areas and S. uniflorum subsp. oryzifolium is only found on sandy seashores. Conclusions Sedum tarokoense H.W. Lin & J.C. Wang is described as a new species. We provide a description, line drawing, and distribution map, as well as photograph, a key and a table to distinguish S. tarokoense from its related species.