Epidermal structures and stomatal parameters of Chinese endemic Glyptostrobus pensilis (Taxodiaceae)

Glyptostrobus pensilis K. Koch, the only living species, is endemic to southern China. Epidermal structures of G .  pensilis have been studied on leaves collected from Guangzhou, southern China, the native locality of the species, and from Hangzhou, eastern China, the cultivated locality. Leaves are linear, linear‐subulate and scale‐like. Epidermal cells are rectangular and elongate parallel to the mid‐vein on areas lacking stomata, and short, with rounded corners, on intrastomatal areas. Stomatal bands lie parallel to the mid‐vein on both surfaces of leaves. Commonly the stomata have five or six subsidiary cells. Stomatal parameters (density and index) of the same surfaces of linear leaves from Guangzhou and Hangzhou show no statistically significant differences ( P  > 0.05). Considering the stomatal parameters of the same surfaces of linear‐subulate leaves between the two localities, the stomatal index of the abaxial surfaces reveals no significant differences ( P  > 0.05), while the stomatal index of the adaxial surfaces and the stomatal density of both surfaces exhibit significant differences ( P  < 0.05). Intra‐individual variation in stomatal index is smaller than that in stomatal density based on the coefficient of variability of stomatal parameters of the same areas of leaves. When studying the correlation between stomatal parameters of G. pensilis and atmospheric CO 2 concentrations, the stomatal parameters of linear leaves are mostly significant, and stomatal index is more useful than stomatal density. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 153–162.