Paphiopedilum and Cypripedium are closely related in phylogeny, but have contrasting leaf traits and habitats. To understand the divergence in leaf traits of Paphiopedilum and Cypripedium and their adaptive significance, we analyzed the leaf anatomical structures, leaf dry mass per area (LMA), leaf lifespan (LL), leaf nitrogen concentration (N mass ), leaf phosphorus concentration (P mass ), mass-based light-saturated photosynthetic rate (A mass ), water use efficiency (WUE), photosynthetic nitrogen use efficiency (PNUE) and leaf construction cost (CC) for six species. Compared with Cypripedium, Paphiopedilum was characterized by drought tolerance derived from its leaf anatomical structures, including fleshy leaves, thick surface cuticles, huge adaxial epidermis cells, lower total stoma area, and sunken stomata. The special leaf structures of Paphiopedilum were accompanied by longer LL; higher LMA, WUE, and CC; and lower N mass , P mass , A mass , and PNUE compared with Cypripedium. Leaf traits in Paphiopedilum helped it adapt to arid and nutrientpoor karst habitats. However, the leaf traits of Cypripedium reflect adaptations to an environment characterized by rich soil, abundant soil water, and significant seasonal fluctuations in temperature and precipitation. The present results contribute to our understanding of the divergent adaptation of leaf traits in slipper orchids, which is beneficial for the conservation of endangered orchids.

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With the purpose of assessing the status of dormancy in seeds of two Begonia species (Begonia lithophila and Begonia guishanensis), freshly matured seeds were given gibberellic acid and moist chilling and allowed to dry after ripening. The seeds were then germinated on media with or without KNO3 at 15, 20, 25, 30 and 18/25°C. All three treatments significantly increased germination percentages. Examination by X‐ray revealed that seeds of both species have a fully developed embryo and thus have no morphological component of dormancy; seeds readily imbibed water and KNO3 solution. Therefore, we conclude that seeds of the two Begonia species have non‐deep physiological dormancy. Although KNO3 significantly increased germination in both species, alternating temperatures did not, suggesting that the most favorable microhabitat for germination is small‐scale disturbances under the forest canopy.

Four new species and two new records of eriophyoid mite species from Nanning, Guangxi Zhuang Autonomous Region, China are described and illustrated: Disella chromolaena sp. nov. infesting Chromolaena odorata (Linnaeus) R. M. King & H. Rob. (Asteraceae); Abacarus oxalis sp. nov. from Oxalis corniculata L. (Oxalidaceae); Tetra radermachera sp. nov. infesting Radermachera sinica (Hance) Hemsl. (Bignoniaceae); Tegonotus microcarpae sp. nov. from Ficus macrocarpa L. f. 'Golden Leaves'. (Moraceae); Aculops morindae Ghosh & Chakrabarati, 1989 rec. nov. from Paederia foetida L. (Rubiaceae); Shevtchenkella longitubercula Mo, Tan & Wang, 2017 rec. nov. from Dimocarpus longan Lour. (Sapindaceae). All mites are vagrants causing no apparent damage to their host plants. We provided mitochondrial COI sequences for Abacarus oxalis sp. nov. (GenBank accession numbers OQ571329 and OQ571330), Aculops morindae Ghosh & Chakrabarati, 1989 rec. nov. (OQ571325–OQ571328), and Tegonotus microcarpa sp. nov. (OQ571323 and OQ571324). A list of eriophyoid mites known from Guangxi University is given.

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