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Premise of research. The geographic origin of Pinus krempfii Lecomte, an unusual pine endemic to Vietnam, is unknown, as are the fossil relatives of this species. Its affinity and classification are also problematic. Morphological and systematic studies have shown that this species differs from all other pines in its falcate, lanceolate, and flat needles. Fossils can provide evolutionary and systematic clues for such extant species. Methodology. Fossil leafy twigs were discovered in the early Oligocene Wenshan flora, Yunnan Province, southwestern China. The morphological variation of these fossils was compared with the morphology of extant species in the genus Pinus. On the basis of these comparisons, the close affinity of the fossils to the extant P. krempfii is discussed. Pivotal results. The Chinese fossils were assigned to P. leptokrempfii sp. nov., which is interpreted as most closely related to extant P. krempfii on the basis of morphological similarities such as falcate and flat needles. It differs from the extant species, which possesses only two-needled fascicles, by possessing two- or three-needled fascicles and longer, narrower needles. Conclusions. Relatives of P. krempfii occurred in the early Oligocene in subtropical mixed mesophytic forests that covered an area corresponding to present-day eastern Asia and eastern and western North America. Since the early Oligocene, global cooling and the monsoon climate in southern China may have induced the southward expansion and differentiation of P. leptokrempfii. The needles of P. krempfii , which are shorter and broader than those of P. leptokrempfii , may have evolved to adapt to the warmer, more humid climate in present-day Vietnam. [ABSTRACT FROM AUTHOR]

A fossil seed cone and associated needles from the upper Miocene Wenshan flora, Yunnan Province, SW China are recognized as Pinus massoniana Lambert, which is an endemic conifer distributed mostly in southern, central and eastern parts of China. The comparisons of these fossils with the three extant variants in this species ( P. massoniana var. shaxianensis Zhou, P. massoniana var. massoniana Lambert and P. massoniana var. hainanensis Cheng et Fu) indicate that the fossils closely resemble P. massoniana var. hainanensis , which is a tropical montane thermophilic and hygrophilous plant restricted to Hainan Island in southern China. The present finding and a previous report of Pinus premassoniana from the same age in southeastern China, which bears close affinities with modern P. massoniana var. massoniana , suggest that the variation in this species arose earlier than was previously thought. Thus, the presence of P. massoniana var. hainanensis in the late Miocene Wenshan flora, Yunnan Province in southwestern China suggests (1) the subdifferentiation of P. massoniana began in the late Miocene or earlier; (2) the extant distribution of P. massoniana var. hainanensis might be derived from northern populations – the major distribution of extant P. massoniana – by southward expansion during Neogene or Quaternary climate changes; (3) disappearance of P. massoniana from southeastern Yunnan in southwestern China is probably related to the intensification of monsoon climate after the late Miocene. [ABSTRACT FROM AUTHOR]

* Premise of the study: The paleogeographical origin of the relict North American Sequoia sempervirens is controversial. Fossil records indicate a Neogene origin for its foliage characteristics. Although several fossils from the Miocene sediments in eastern Asia have been considered to have close affinities with the modem S. sempervirens, they lack the typical features of a leafy twig bearing linear as well as scale leaves, and the fertile shoots terminating by a cone. The taxonomic status of these fossils has remained unclear. * Methods: New better-preserved fossils from the upper Miocene of China indicate a new species of Sequoia. This finding not only confirms the former presence of this genus in eastern Asia, but it also confirms the affinity of this Asian form to the modern relict S. sempervirens. * Key results: The principal foliage characteristics of S. sempervirens had already originated by the late Miocene. The eastern Asian records probably imply a Beringian biogeographic track of the ancestor of S. sempervirens in the early Neogene, at a time when the land bridge was not too cool for this thermophilic conifer to spread between Asia and North America. * Conclusions: The climatic context of the new fossil Sequoia in Southeast Yunnan, based on other floristic elements of the fossil assemblage in which it is found, is presumed to be warm and humid. Following the uplift of the Qinghai-Tibet Plateau, this warm, humid climate was replaced by the present monsoonal climate with dry winter and spring. This change may have led to the disappearance of this hygrophilous conifer from eastern Asia. [ABSTRACT FROM AUTHOR]

Schizolepis daohugouensis sp. nov. is described from the Jurassic sediments of Daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3-5 mm. The seed scales are bilobed and divided almost from the base; the scales have no evident petiole but an articulation at the region of attachment to the cone axis. Each lobe of the seed scales is oval in shape, widest at the lower middle part; lobes are obtusely pointed with entire margins. Bract scale is fan shaped. Based on the records of Schizolepis, this is the first report of the occurrence of female cone of Schizolepis with the seed scales, the winged seeds and vegetative branches preserved together in the Jurassic deposits. The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae. [ABSTRACT FROM AUTHOR]

The diversification of the relict genus Calocedrus Kurz (Cupressaceae) in the Neogene of eastern Asia has remained unknown due to lack of fossil evidence. A late Miocene species, Calocedrus shengxianensis (He, Sun et Liu) Zhang et Zhou comb. nov., is described on the basis of new fossil material from the Wenshan flora in SE Yunnan, SW China. The species was originally described as Fokienia shengxianensis He, Sun et Liu from the upper Miocene Shengxian flora in E Zhejiang, SE China. The new fossil material includes well-preserved compression of leafy shoots and associated impression of seed cones. Based on the comparisons, this fossil species bears most similarities to the modern Calocedrus macrolepis Kurz, which is presently endemic to eastern Asia, in N India, Laos, NE Myanmar, NE Thailand, Vietnam and S China, but does not occur in SE Yunnan and E Zhejiang. The difference between them lies primarily in the morphology of apex of lateral as well as facial leaves. With the global cooling and uplift of the Qinghai–Tibet Plateau since the late Miocene, the climate in eastern Asia has changed profoundly. This has led to the disappearance of C. shengxianensis from SE Yunnan and E Zhejiang, and the leaf morphological shifts in C. macrolepis : the acute or acuminate leaf apices in the modern C. macrolepis , which are in contrast to the blunt or obtuse ones in the late Miocene C. shengxianensis , have evolved probably to adapt to the humid climate since the late Miocene. [ABSTRACT FROM AUTHOR]