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Pollen morphology of 26 taxa of Clerodendrum, as well as one species of Volkameria from China, was investigated through a scanning electron microscope (SEM). Pollen grains of Clerodendrum are monads, radiosymmetric and tricolpate, with medium or large size. The equatorial view of the pollen grains is spheroidal or subprolate and the polar view is (sub) circular or rounded triangular. The colpus membrane of the investigated taxa is sunken (rarely even). Five varying pollen types are delimited on the basis of exine sculpturing: (1) spine-tectum perforatum; (2) spine-tectum imperforatum; (3) microspine- tectum perforatum; (4) microspine-tectum imperforatum; and (5) obtuser spine. The results indicate that Clerodendrum is closely related to several genera in Lamiaceae, including Aegiphila, Amasonia, Kalaharia, Tetraclea, Volkameria, Oxera, Faradaya, and Hosea, as supported by previous phylogenic studies. Additionally, the conventional infrageneric classification of Clerodendrum based on inflorescence and leaf characters is not supported by the results. However, the palynological data can be used to identify some closely related species with similar external characteristics. In conclusion, the investigation of pollen morphology not only contributes novel data from palynology for Clerodendrum but also provides a basis for future comprehensive classification of this genus. [ABSTRACT FROM AUTHOR]

This paper describes and illustrates the morphological traits of Impatiens zhaojueensis Q. Luo (Balsaminaceae), a new species from the Sichuan Province of southwestern China. Using a scanning electron microscope (SEM), the micromorphological characteristics of its pollen grains and seeds are also described. The new species is closely related to Impatiens baishaensis, but it has larger flowers, obround dorsal petals, somewhat clawed lateral united petals, obround or obround‐dolabriform distal lobes and the ornamentation on the pollen grains has wider meshes. [ABSTRACT FROM AUTHOR]