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Machilus maomingensis Jin et Tang, sp. nov. from the Eocene Youganwo Formation of the Maoming Basin, South China, is studied in detail from the perspective of the leaf architecture and the excellently preserved cuticle. The leaf margin is entire, the primary venation is pinnate; 6 to 8 secondary veins are present and the major secondary venation is eucamptodromous. Stomata are paracytic and occur on the lower epidermis. Trichome bases are unicellular. Oil cells are present in the upper epidermis. The new fossil species described has features of the Lauraceae, particularly of the extant genus Machilus Rumphius ex Nees, and it is most similar to Machilus chinensis (Bentham) Hemsley, an extant species distributed in southern China and Vietnam. Hence, Machilus maomingensis sp. nov. is inferred to live in a warm and humid climate. The discovery of the present fossil indicates that Machilus has existed in South China from at least the Eocene. [ABSTRACT FROM AUTHOR]

Premise of research. Petrified wood has never been described from the Miocene of South China, and the Miocene flora from this region is also poorly known. The fabaceous fossil wood introduced in this article not only contributes to the scant knowledge of petrified woods in South China but also provides significant fossil evidence to study the Miocene floristic diversity in the modern tropical area of China. Methodology. Anatomically preserved petrified woods collected from the Early-Middle Miocene of Jialai-Nanbao Basin, Hainan Island, were sectioned in accordance with standard methods of cutting, grinding, and polishing. We determined their taxonomic positions based on comparative work in anatomy with similar extant and fossil wood slides. Pivotal results. Woods in two different degrees of fossilization represent the same species and correspond closely to wood structure of modern genera Afzelia and Intsia and their fossil counterparts Pahudioxylon. The wood is recognized as Pahudioxylon bankurensis Chowdhury, Ghosh, et Kazmi, which had been reported from the Neogene of India. Six species of Pahudioxylon (P. sahnii Ghosh et Kazmi, P. deomaliense Prakash, P. welkitii Lemoigne et Beauchamp, P. assamicum Prakash et Tripathi, P. indicum Prakash, and P. bengalensis Ghosh et Roy) have been reconsidered as its synonyms. Conclusions. This studied Pahudioxylon species represents the first occurrence of this genus in China as well as rarely reported Miocene plant megafossils in South China. Several previously described Pahudioxylon species should be merged into P. bankurensis. [ABSTRACT FROM AUTHOR]

* Premise of the study: Dipterocarps are the representative component of tropical rain forests in Southeast Asia and hold important economic and ecological significance, but their origin and migration are controversial. Information on dipterocarpaceous fossils, particularly the more convincing reproductive structures, not only can improve the phylogenetic and phytogeographic studies of this family, but also provide important information for reconstructing paleoclimate. * Methods: Morphologically preserved winged fruits and associated leaves were collected from the Late Eocene Huangniuling Formation, Maoming Basin, South China. We determined their taxonomic positions based on comparative morphology with similar extant and fossil specimens and discuss their phytogeographic and paleoclimatic implications by consulting the distribution and habitat of fossil and modern populations. * Key results: The Late Eocene winged fruits are attributed to Shorea Roxburgh ex Gaertner (Dipterocarpaceae) as Shorea maomingensis sp. nov. The associated leaves are recognized as Shorea sp. based on leaf architecture, and they are likely to be conspecific with the winged fruits. * Conclusions: The discovery of dipterocarps indicates that they had arrived in tropical and humid South China by the Late Eocene. Dipterocarps including Shorea exhibit a wide range of physiological tolerance to climate; palynological analysis suggests an increase in aridity and seasonality in the Maoming Basin from the Late Eocene. Dipterocarps became adapted to this seasonal climate from the Late Eocene to Early Miocene, expanded northward in the climatic optimum of the Middle Miocene, and declined and gradually disappeared from the southeastern part of the continent from the Late Miocene. [ABSTRACT FROM AUTHOR]

Abstract: Two types of fossil fruit, one belonging to Palaeocarya sp. (Juglandaceae) and the other to Acer cf. A. miofranchetii Hu et Chaney (Aceraceae), are found in the Eocene coal-bearing series from the Changchang Basin of Hainan Island, China. This is the first fossil record of Palaeocarya and Acer in a tropical area of China. These fossils provide evidence for an investigation of the phytogeographic history of these two genera. Since their extant relative genera are distributed mostly in northern temperate or tropical–subtropical mountainous regions, I propose that the Changchang Basin of Hainan Island was close to a mountainous region in the Eocene; the plants bearing these fruits were growing at a mid-high altitude with a relatively cool climate, and the fruits were not preserved in situ but transported to the fossil site. The characters of other associated fossil plants and palynological data also support this hypothesis. [Copyright &y& Elsevier]

• This study summarizes all existing and unpublished data on the Late Triassic plant fossils in Guangdong. • Four regional assemblages have been distinguished in the Late Triassic by marine fossils such as ammonites and bivalves. • The Late Triassic climate in the Guangdong region was mainly warm and humid, either tropical or subtropical. • During the Late Triassic, central and northern Guangdong were located at similar latitude, along the southern coastline of the South China Block. Triassic-Jurassic deposits are well developed in Guangdong Province, South China. In particular, the Upper Triassic coal-bearing strata which alternate between marine and terrestrial deposits yield diverse and abundant fossil plants, ammonites and bivalves. These strata provide a significant reference for the study of palaeoenvironmental variations in the lower latitude regions. In this paper, we review the major progress on Late Triassic floral studies in this area. Specifically, we compare the regional plant assemblages from different fossil sites in central and northern Guangdong which have been dated with marine fauna. 155 species belonging to 56 genera of fossil plants have been reported so far in northern and central Guangdong. The Late Triassic floras in Guangdong are mainly composed of Bennettitales and ferns, followed by horsetails, seed ferns, cycads, ginkgos and conifers. In ascending order, four regional plant fossil assemblages can be recognized in the Late Triassic deposits, namely the Pachypteris - Lindleycladus Assemblage (Julian), the Pterophyllum - Baiera Assemblage (late Julian), the Clathropteris - Otozamites Assemblage (Tuvalian), and the Danaeopsis - Anomozamites Assemblage (Rhaetian). In general, the Late Triassic climate in the Guangdong region was mainly humid and warm and either tropical or subtropical. The fossil plants corroborate palaeomagnetic evidence that the central and northern Guangdong region was located at approximately the same latitude as it is today and formed the southern coastline of the South China Block during the Late Triassic. Palaeogeographically, the transgression started at the end of the Julian and the south coastal terrane consisted of a western bay, a peninsula and an eastern bay. During the regression period, post-Rhaetian, the bays evolved into a gulf coastal plain. [ABSTRACT FROM AUTHOR]

Abstract A new species of the genus Cunninghamia (Cupressaceae s.l.) is reported from the Lower Oligocene Shangcun Formation of the Maoming Basin, Guangdong Province, South China based on compressions/impressions of leafy shoots and an isolated leaf. Cunninghamia shangcunica sp. nov. possesses helically arranged and radially spread polymorphic leaves. Most Cretaceous cunninghamioid species exhibits a similar phyllotaxis with this new species, and it can be regarded as a primitive character. In the Miocene species, terminal shoots with a bilateral (pectinate) arrangement of leaves predominated. The new species is similar to the extant species C. konishii in shoot and leaf morphology, and to С. lanceolata in the characters of the epidermis. The new Oligocene species increases the known diversity of the genus Cunninghamia in its refugial region and contributes to a greater understanding of the specific variability and ecology of this conifer. A diverse population of epiphyllous fungi on the leaves of the new species are recorded and figured. Highlights • Cunninghamia foliage with well-preserved cuticle from the Oligocene of South China. • New species with helically arranged and radially spread polymorphic leaves. • The earliest fossil record of Cunninghamia in China. [ABSTRACT FROM AUTHOR]

The study of fossil plant–biotic (mainly arthropod) interactions offers an opportunity to understand the evolutionary process in palaeoecosystems and their response to climate fluctuation. Despite the importance of such investigations, not much is known about plant–arthropod associations from the Cenozoic floras of Asia. Exceptionally diverse Eocene floras from adjacent Maoming and Changchang sedimentary basins of southern China provide valuable insights into low-latitude palaeoecosystems. These floras indicate different intensities of plant–arthropod interactions and probably viral, bacterial or fungal infection. Two upper Eocene floras from the Maoming Basin are markedly distinct from two approximately contemporaneous middle Eocene floras of the Changchang and Maoming basins in exhibiting much more abundant and diverse plant damage types (DTs). For equivalent comparisons we focus on well-sampled fossil leaves of Liquidambar L. (Altingiaceae) present and relatively abundant in both basins. L. maomingensis and Liquidambar sp. 1 from both upper Eocene Maoming floras exhibit mainly external foliage feeding. In contrast, almost only galling occurs on Liquidambar sp. 2 leaves from the middle Eocene Changchang flora. The differences in the diversity and frequency of DTs in the studied palaeofloras could have been affected by a progressive warming and increase in climate seasonality over the middle–late Eocene interval as well as by habitat conditions and plant successional status. We hypothesize that L. maomingensis and Liquidambar sp. 1 from the Maoming Basin inhabited the early successional riparian forests on an alluvial plain, whereas Liquidambar sp. 2 from the Changchang Basin was a component of more mature plant communities. [ABSTRACT FROM AUTHOR]