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The genus Impatiens comprises more than 1000 species and displays enormous morphological diversity. As a taxon that is notoriously difficult to classify morphologically, the taxonomic significance of pollen morphology has been discussed in previous studies. However, there was only limited study on the evolution of palynological and macroscopic character in this genus before. In this paper, we observed pollen of 143 species of Impatiens, including all representatives of infrageneric groups and discussed their taxonomic value. Meanwhile, based on the reconstructed phylogenetic framework, we selected five pollen traits, and nine macroscopic traits including both vegetative and reproductive organs for evolutionary analysis. The character reconstruction showed that the morphology and number of aperture, granules in lumina, seed number of per capsule, number of sepals, lateral united petals connate, spur length, and phyllotaxy could be identified as unambiguous, while other characters were ambiguous in the last common ancestor of Impatiens. The results of comprehensively macroscopic characters and palynological evidence suggest that these traits experienced a complicated evolution, exhibit high levels of instability and variability and occur character multiple reversals in the evolutionary processes of Impatiens due to different selection pressures. In addition, we found that there is an evident mosaic evolution in this genus. Pollen and macroscopic character are conserved with a slower evolutionary rate in the I. subgen. Clavicarpa, however, these characters showed higher diversity with a rapid rate of evolution in the I. subgen. Impatiens. Furthermore, the relationship between floral morphology and pollinators was discussed. [ABSTRACT FROM AUTHOR]

Impatiens is one of the most species-rich genera of angiosperms, with more than 1,000 species distributed in Eurasia and Africa. Previous studies have shown that seeds of Impatiens display enormous morphological diversity, and seed micromorphology may contribute to the classification of those species. However, the micromorphological seed coat characteristics of Impatiens seeds have not been systematically studied. In this study, we examined 117 Impatiens seeds from two subgenera and seven sections, and analyzed the seed characters of shape, primary ornamentation, secondary ornamentation, anticlinal cell wall, and periclinal cell wall. We discovered that, according to the different shapes of ornamentation, seed coat can be divided into three types, viz, reticulate type, protrusive type, appendicular type, and that they can be further subdivided into 10 subtypes. In addition, the characteristics of seed coat ornamentation with taxonomic significance in this genus are discussed. We reconstructed the ancestral states of the above seed characters of the Impatiens using the maximum likelihood approach based on the reconstructed phylogenetic framework. The seed character reconstruction showed that the seed shape, primary ornamentation, and anticlinal cell wall could be identified as unambiguous, while other characters were ambiguous in the last common ancestor of Impatiens. Reconstruction of important seed morphological characters showed that the secondary ornamentation possesses high plasticity, and the primary ornamentation has high homology. In addition, we inferred the evolutionary trends of seed ornamentation and found that the seed coat ornamentation of Impatiens experienced a complex evolutionary process from a reticulate type into more complex types. We also discussed the relationship between seed coat diversity vs. environmental adaptation and seed dispersal in Impatiens. [ABSTRACT FROM AUTHOR]

Impatiens shangjiangensis Y.Y. Cong & J.Z. Gu, a new species of Balsaminaceae from Lushui County, Yunnan, China, is described and illustrated. It is similar to I. bahanensis, but differs from it in having bigger flowers, a curved-saccate lower sepal, and a reniform dorsal petal. Pollen grains are also different in the two species. [ABSTRACT FROM AUTHOR]

Impatiens rapiformis (Balsaminaceae), a new species from Malipo County, Yunnan, China, is described and illustrated. The new species is superficially similar to I. apalophylla, I. malipoensis and I. guizhouensis, but differs by having cylindric or subfusiform root tuber, elliptic or obovate‐oblong leaf blades and falcate outer lateral sepals. The characters of its seed micromorphology and pollen morphology under SEM are given. A preliminary molecular phylogenetic study suggests that I. rapiformis should be placed in I. subg. Clavicarpa. [ABSTRACT FROM AUTHOR]

Impatiens longshanensis (The LSID for the name Impatiens longshanensis is: 77219154-1) sp. nov. and I. lihengiana (The LSID for the name I. lihengiana is: 77219153-1) sp. nov., from Hunan, China, are described and illustrated here. The molecular phylogenetic study suggests that I. longshanensis and I. lihengiana should be placed in the I. sect. Impatiens. A detailed description, diagnostic characters between the two new species and allied species, pollen and seed morphology, and color photographs are provided. In addition, based on wide sampling, we found that the longifilamenta group, an endemic group to China, whose members have basal lobes of lateral united petals with long filamentous hairs, shows significant morphological variability. In this paper, we discuss the taxonomic significance of morphological characteristics within this group. Based on a literature review and observation of living materials in the field, an updated identification key for this group is also proposed. [ABSTRACT FROM AUTHOR]

Bupleurum , belonging to the Apiaceae, is widely distributed across the Eurasian continent. The origin and species diversification of Bupleurum in East Asia, remain incompletely resolved due to the limited samples in previous studies. To address these issues, we have reconstructed a robust phylogenetic framework for Bupleurum in East Asia based on the ITS and three plastid genes. Our phylogenetic analysis confirms the monophyly of Bupleurum with strong support. Both ITS and chloroplast dataset divided the Bupleurum in East Asia into East Asia Group I and East Asia Group II in this study. The divergence time and ancestral area reconstruction of ITS dataset indicated that the Bupleurum originated in the Mediterranean basin and its adjacent areas around 50.33 Ma. subg. Penninervia and subg. Bupleurum diverged at about 44.35 Ma, which may be related to the collision of India with the Eurasian continent. Both East Asia Group I and East Asia Group II originated from a common ancestor in the Mediterranean, East Asia Group I divergence around 12.95 Ma; East Asia Group II divergence around 13.32 Ma. The character reconstruction showed that the morphological characters and altitude distribution analyzed in this study exhibit a scattered distribution in East Asian Group I and East Asian Group II. Additionally, diversification rate analysis shows that the East Asian Group I and East Asian Group II exhibited no significant shifts in diversification rates in the evolutionary history according to ITS and combined dataset. Both molecular and morphological data supports that East Asian Bupleurum is a museum taxon, meaning that the species diversity of East Asian Bupleurum has gradually accumulated over time., Competing Interests: The authors have declared that no competing interests exist., (Yong-xiu Song, Ceng-yue Yang, Yu-Yang Zhou, Yan Yu.)