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Paliurus (Rhamnaceae) is a small genus with a narrow and disjunct distribution in East Asia and the Mediterranean. Fossil evidence from the Late Cretaceous to the present suggests it once had a broad geographic distribution, encompassing parts of India, North America, Asia, and Europe. To reconstruct the evolutionary history of Paliurus and understand the origin of the disjunction observed today in the Northern Hemisphere, phylogenetic and biogeographical reconstructions were performed based on ITS, trnL-F, and rbcL sequences. Paliurus is shown to be a monophyletic genus, which could be divided into two clades as suggested by previous studies. Biogeographical inference integrated with fossil information indicates that the origin and dispersal pattern of the genus coincide with the "Out-of-India" hypothesis. The genus may have originated in India or other parts of Gondwana and then dispersed to East Asia after the collision of the Indian subcontinent with Eurasia, and to North America via the Bering land bridge. Paliurus appears to have reached the Mediterranean region in the late Oligocene following closure of the Turgai Strait. The uplift of the Qinghai-Tibet Plateau and the advent of drying and cooling climates during the Miocene may have fragmented the distribution of the genus, shaping the biogeographical patterns observed today. Paliurus populations in different regions either became extinct or adapted to changes in local ecological conditions following global climatic shifts through geological time. [ABSTRACT FROM AUTHOR]

Abstract: A new species of Cucubalus is described based on two fossil seeds recovered from the upper Pliocene Sanying Formation in northwestern Yunnan Province, southwestern China. The seeds are characterized by a reniform to circular outline in shape, and sinuous and discontinuous rugulae made of rod-like elements radiating from the hilum region to the dorsal margin. The combination of these characteristics shows their close resemblance to the extant genus Cucubalus in the Caryophyllaceae. A morphological principal coordinates (PCO) analysis further supports the assignment to this genus. Cucubalus is a monotypic genus today, but the late Pliocene fossil seeds have been described as a new species, Cucubalus prebaccifer Huang, Liu et Zhou, sp. nov. This newly documented Cucubalus fossil, representing the first fossil record of this genus, implies that the genus has existed in northwestern Yunnan, southwestern China, at least since the late Pliocene. It provides important information on the past biodiversity and biogeography of both the genus Cucubalus and the fossil-scant family Caryophyllaceae. [Copyright &y& Elsevier]

Abstract: The Miocene climate evolution in North China is preliminarily discussed by means of comparisons in seven climate parameters quantitatively reconstructed by the Coexistence Approach on 34 selected macro- and microfloras over North China. The Miocene temperatures show no great difference in the western and eastern part of North China. Temperature fluctuations, particularly in mean annual temperature, are found within floras from several sites. The fluctuation pattern, from a climate optimum in the Mid Miocene to cooling decline in the Late Miocene, is generally consistent with the global trend of Miocene temperature change. The reconstructed precipitation from all the sites studied shows much wetter conditions in North China during the Miocene than at present, which corroborates the results from paleoprecipitation proxy of fossil mammals. Like the situation in paleo-temperature, the Miocene precipitation from North China shows no distinct difference between the western and eastern regions. It is suggested that North China, particularly in the western part, was by no means under an arid or semi-arid environment during the Miocene. North China is an ideal region for study of the impact of the East Asian monsoon system, however, the pattern of precipitation change derived from the monsoon index (MSH) and mean annual precipitation (MAP) shows contradictory results. Therefore, there appears no definite conclusion on when the East Asian summer monsoon intensified. Possible reasons for inconsistency in temperature and precipitation changes are discussed. Directions of future work to improve the resolution of climate evolution are also pointed out. [Copyright &y& Elsevier]

Abstract: Twenty-one fossil foliage, identified as Fokienia shengxianensis sp. nov. (Cupressaceae), were collected from the upper Miocene Shengxian Formation in Tiantai and Ninghai counties, Zhejiang Province of eastern China. These fossils can likely be distinguished from other extant genera in the family Cupressaceae s.l. except Fokienia by leaf external morphology alone. Foliar cuticular comparison with the only modern species in this genus, Fokienia hodginsii Henry et Thomas, further suggests that the present fossil species closely resembles the modern counterpart. Paleoecologically, the occurrence of Fokienia from the Shengxian Formation appears to support that the fossil site was covered by subtropical evergreen broad-leaved forest and under warm and humid conditions during the late Miocene, consistent with evidence from previously published fossil plants. [Copyright &y& Elsevier]

Abstract: A new species of fossil endocarp is described from the Sanying Formation of the upper Pliocene at Fudong Village, Lanping County of northwestern Yunnan Province, Southwest China. The endocarps are elliptic, ovate or oblong elliptic, 2.1–2.5mm long and 1.2–1.7mm wide. The dorsal face is convex and the ventral is concave or more flattened. The endocarp surface is loosely, transversely or sinuously furrowed and ridged, forming a reticulate and alveolate pattern on the ridges, and the inner wall of the surface cells on the ridges is flaky and scaly. They are morphologically compared with selected extant genera of Adoxaceae and Caprifoliaceae. The interspecific comparisons show diagnostic differences of the fossil endocarps from the selected modern species and other fossil taxa, supporting their recognition as a new species: Sambucus alveolatisemina Huang, Liu et Zhou, sp. nov. Previous records of the reliable Sambucus fossils were from mid-high latitude regions in Europe, northeastern Asia and northern North America. Therefore, it is interesting to note that S. alveolatisemina represents a fossil record from a low latitude region. Sambucus apparently has existed at low latitudes in China at least since the upper Pliocene. A review of other Sambucus fossil occurrences indicates that plants of this genus have been living at higher latitudes in the geological past than they are at present. [Copyright &y& Elsevier]

Abstract: Neogene climates and vegetation history of western Yunnan are reconstructed on the basis of known fossil plants using the Coexistence Approach (CA) and Leaf Margin Analysis (LMA). Four Neogene leaf floras from Tengchong, Jianchuan and Eryuan in southwestern China are analyzed by the CA, and the paleoclimatic data of one Miocene carpoflora from Longling and three Pliocene palynofloras from Longling, Yangyi and Eryuan are used for comparison. The Miocene vegetation of the whole of West Yunnan is subtropical evergreen broad-leaved forest, and a similar mean annual precipitation is inferred for Tengchong, Longling and Jianchuan. However, by the Late Pliocene a large difference in vegetation occurred between the two slopes of Gaoligong Mountain, western Yunnan. The region of Tengchong retained a subtropical evergreen broad-leaved forest vegetation, whereas in Yangyi and Eryuan a vertical vegetation zonation had developed, which consists, in ascending order, of humid evergreen broad-leaved, needle and broad-leaved mixed evergreen, and coniferous forests. Distinctively, the Late Pliocene vegetational patterns of West Yunnan were already very similar to those of the present, and the Pliocene mean annual precipitation in Tengchong was markedly higher than that of Yangyi and Eryuan. Considering that the overall vegetation of West Yunnan and the precipitation at Yangyi and Eryuan have undergone no distinct change since the Late Pliocene, we conclude that the Hengduan Mountains on the northern boundary of West Yunnan must have arisen after the Miocene and approached their highest elevation before the Late Pliocene. Furthermore, the fact of the eastern portion of the Tibetan Plateau underwent a slight uplift after the Late Pliocene is also supported. [Copyright &y& Elsevier]

Abstract: Plant fossils from the Citronelle Formation provide a rare window into the Pliocene flora and climate of the northeastern Gulf of Mexico Coastal Plain. Many of the taxa recovered to date inhabit the region today. However, analysis of Pinus pollen grains and fascicles indicates that the dominant pines were members of Pinus subgenus Strobus (i.e., “white pines”). The fascicles have a small, bulbous base lacking a sheath, and bear four or five long, slender needles. These features are typical of white pines. Although macrofossils are rare, 77 to 100% of the dispersed Pinus pollen grains from five localities have sacci continuous with the corpus and verrucae on the cappula, which are characteristics of white pines. This is remarkable, as the northeastern Gulf of Mexico Coastal Plain today is devoid of white pines, and is instead considered a center of diversity for Pinus subgenus Pinus section Pinus subsection Australes. Today, Pinus strobus is the only white pine in the eastern North America and its southernmost distribution only extends into the mountains of Georgia, about 600km north of the fossil sites. The historical biogeographic relationships of P. strobus to other North American forms are unclear. For example, its close relative, Pinus chiapensis, is present in northeastern Mexico and Central America. The current disjunction between P. strobus and P. chiapensis is 2400km and includes an arid barrier to dispersal. P. chiapensis is also associated with several other species showing a similar biogeographic pattern. The fossils described here indicate that white pines were more widespread in North America in the recent geological past than previously thought, and imply possible connections between disjunct species that would not be suspected if only current species'' ranges and ecological tolerances were considered. [Copyright &y& Elsevier]

Abstract: The late Miocene Xiaolongtan megaflora from Kaiyuan in southeast Yunnan (23°48′45″N, 103°11′52″E, 1050 m a.s.l.) was chosen for palaeoclimatic reconstruction using three quantitative techniques, i.e. the Coexistence Approach (CA), Leaf Margin Analysis (LMA), and the Climate–Leaf Analysis Multivariate Program (CLAMP). The reconstructed climatic parameters are also compared with those of the two adjacent Miocene floras currently available in Yunnan, i.e. the early to middle Miocene carpological Mangdan flora (24°24′N, 97°49′E, 1620 m a.s.l.) and the late Miocene Lühe palynoflora (25°10′N, 101°22′E, 1930 m a.s.l.). Quantitative analyses of the Xiaolongtan flora supports the previous qualitative results of a southern, humid subtropical climate, being more humid and having a slightly higher mean annual temperature (MAT) than today. The MATs calculated by CA, LMA, and CLAMP overlap (16.7–19.2 °C, 22.3±2.05 °C, 18.1±1.2 °C, respectively) and are close to the present day value (19.7 °C). The overlapping of temperatures derived using the three techniques is unusual and probably related to the low latitude of the Xiaolongtan area and the southern subtropical nature of its vegetation. Both the mean temperatures of the warmest month (WMT) and of the coldest month (CMT) reconstructed by CA (WMT=25.4–26.0 °C, CMT=7.7–8.7 °C) and CLAMP (WMT=25.9±1.6 °C, CMT=10.8±1.9 °C) are similar to those of today (WMT=24.3 °C, CMT=12.8 °C), but great changes appear in the mean annual precipitation (MAP). The CLAMP results suggest a higher precipitation (1964±335.9 mm) than CA (1215–1639 mm), but they are much higher than the present MAP (820.5 mm). This is consistent with results from the Lühe palynoflora, which also developed under a warmer subtropical climate with higher precipitation (803.6–1254.7 mm) than that of today (815.9 mm). In contrast, the Mangdan flora, situated in a more complicated topographic region to the west of Xiaolongtan and near the Sino-Myanmar border, implies a slightly lower precipitation (1170–1300 mm) than that of today (1300–1400 mm). Overall, the wetter climate during the late Miocene around the Xiaolongtan area suggests that the Himalayas had not yet uplifted to its present altitudes at that time. [Copyright &y& Elsevier]