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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 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]