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The extensive pollen morphological diversity of the Cichorieae has been widely demonstrated, and previous studies have shown that in some cases pollen characters can contribute to our understanding of inter-generic relationships. This paper extends the range of genera for which pollen morphological information is available in two predominantly Old World sub-tribes, Crepidinae and Lactucinae. All the genera discussed were found to produce pollen belonging to previously described types. However, the inclusion of certain, previously under studied Asian genera and species, especially those from China, provides useful new information about the extent of pollen morphological diversity within and between genera in these subtribes, and may contribute to a better understanding of the systematics of these groups. [ABSTRACT FROM AUTHOR]

A newly discovered fossil pollen taxon is described as Lagerstroemia cathayensis sp. nov. on the basis of a combination of morphological characters including prolate shape with no or weakly developed pseudocolpi and rugulate-verrucate tectum. The fossil pollen was recovered from a Miocene deposit in Zhejiang province, eastern China. It resembles pollen of extant Lagerstroemia subcostata Koehne and L. limii Merrill, both species still occurring near the fossil site in Zhejiang province and further extending into other regions of southern China, Japan, India and the Philippines. This record represents the only description of Cenozoic pollen grains of the genus Lagerstroemia from East Asia examined by means of scanning electron microscopy. The occurrence of Lagerstroemia together with some temperate plants (i.e. Keteleeria, Acer, Carpinus, Fagus) at the fossil site suggests that the climate in eastern China during the Miocene was similar to that of today. [ABSTRACT FROM AUTHOR]

The northern slopes of central Tianshan Mountains in Xinjiang, northwestern China can provide an ideal database to research palaeoclimate as disturbance by human impact is relatively low and the vegetation zones reflect climatic gradients. In order to establish the correlation between modern climatic factors and surface pollen assemblages and to reconstruct palaeoclimate on the northern slope of central Tianshan Mountains, three Holocene sections in Daxigou, Huashuwozi and Sichanghu located at different elevations and vegetation zones were chosen for study. A total of 80 surface pollen samples in 86 vegetation quadrats were collected for pollen-vegetation relationship analysis. The Warmth Index (WI) and Moisture Index (MI) were calculated based on averaged modern climate data during 1951 - 2000 at eight weather stations in the study area. Pollen percentages of Picea, Artemisia, Chenopodiaceae, Ephedra, and Tamarix, as well as A/C (Artemisia/Chenopodiaceae) and AP/NAP (arboreal/nonarboreal pollen) ratio were selected as pollen variables and WI and MI were chosen as climatic variables. The relationship between pollen percentages (Picea, Artemisia, Chenopodiaceae and Tamarix), A/C, AP/NAP ratio, WI and MI values were estimated (95% confidence interval) using stepwise multiple linear regression analysis. WI and MI values for the three sections were calculated using these regression equations, and palaeoclimate for the study area could be reconstructed. The results showed periods of both cool-humid and warm-dry conditions on the northern slopes of Tianshan Mountain during the late Holocene. [ABSTRACT FROM AUTHOR]