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Taxonomy of Cinnamomum Schaeff. of Lauraceae remains problematic because recent phylogenetic studies have suggested that this genus is not monophyletic. In this study, we assembled three sequence matrices including plastomes (datamatrix I), nrITS sequences alone (datamatrix II), and nrITS plus plastid psbA‐trnH sequences (datamatrix III) of the Cinnamomum‐Ocotea complex of Lauraceae and conducted a new phylogenetic study with thusfar the most extensive species sampling of the Cinnamomum‐Ocotea group. We determined that the Old World Cinnamomum is diphyletic: sect. Camphora Meisn. is sister to Sassafras J.Presl and sect. Cinnamomum is sister to the African Kuloa Trofimov & Rohwer. A recent study indicated that characters of leaf micromorphological anatomy can define the two clades: one possessing reticulate periclinal and the other having non‐reticulate periclinal walls. As result, we divided the genus Cinnamomum of Lauraceae into two genera, i.e., Cinnamomum and Camphora Fabr. The generic name Cinnamomum is retained for those species mainly having reticulate periclinal epidermal cell walls, inconspicuous non‐perulate terminal buds and usually tripliveined leaves; the oldest generic name, Camphora, is applied to the second group which contains those species mainly possessing non‐reticulate periclinal epidermal cell walls, prominent perulate terminal buds and pinnately‐veined leaves. A census of the species and their type specimens listed under Cinnamomum in Asia resulted in the transfer of 18 species to Camphora, including 15 new combinations. Cinnamomum is diphyletic according to a new phylogeny using nrITS and psbA‐trnH sequences. As a result, we classify the genus Cinnamomum into two genera, i.e., Camphora and Cinnamomum.

Unlike plains, mountains provide diverse habitats for various biomes due to complex topography and large altitudinal differences. It is crucial for objectively reconstructing deep‐time biodiversity changes that the pollen source, dispersal, and driving forces in montane ecosystems are studied. Here, we investigate surface soil samples from different vertical zones in the Hengduan Mountains. Results show the pollen assemblages generally reflect the dominant components of the warm temperate coniferous forest and the cold temperate coniferous and sclerophyllous oak mixed forest, but exotic anemophilous pollen like Pinus (53.4%), Alnus (3.5%), Tsuga (1.1%), and Juglans (0.5%) are found in the subalpine scrub and meadows by upslope flow. The atmospheric reanalysis data suggests that the Asian summer monsoon and diurnally‐varying orographic winds may jointly drive the upslope and downslope pollen flows. These new findings provide basic scientific data and potential interpretations for the reconstructions of past vegetation and plant diversity in global montane ecosystems. Plain Language Summary The origin and evolution of plant diversity in montane ecosystems at global biodiversity hotspots is of great importance to the scientific community. Research on modern pollen depositional processes provides indispensable data for reconstructing past plant diversity. We reveal the pollen source, dispersal, and driving forces in montane ecosystems in the biodiversity hotspot of southwestern China. The Asian summer monsoon and diurnal orographic winds jointly drive the pollen flow. Our new findings provide scientific data and potential interpretation for deep‐time reconstruction of vegetation and plant diversity in montane ecosystems throughout the world. Key Points Exotic anemophilous pollen grains from low altitude are found in the subalpine scrub and meadows by upslope flow The Asian summer monsoon and diurnally‐varying orographic winds may jointly drive the upslope and downslope pollen flows in the region

The type of Cycas debaoensis Y.C.Zhong & C.J.Chen ( Y.C.Zhong 8762 ) consists of nine duplicates in PE. Our new investigation of the type collection suggests that the type includes at least two different gatherings which should be considered as syntypes. For nomenclatural purposes, we lectotypify the name Cycas debaoensis with the herbarium sheet PE00047578 and consider other duplicates in PE and GXMI as isolectotypes. The seeds in the capsule ( Y.C.Zhong s.n. collected in Oct 1998) are considered as a syntype.

Background Male cones of modern Ephedraceae are compound and compact. No fossil evidence has so far been found to support an origin of the compact compound male cone from a hypothetical loosely-arranged shoot system. Results Here we describe a new macrofossil taxon, Eamesia chinensis Yang, Lin, Ferguson et Wang, gen. et sp. nov., from the Early Cretaceous of western Liaoning, northeastern China. It was an ephedroid shrub bearing male spikes terminal to twigs, but differs from modern Ephedraceae by its loosely-arranged male cones, the axillary male shoot consisting of an elongated synangiophore on which leaf-like foliar organs were inserted, and four sessile synangia terminal to the apex. Conclusions The morphology of this fossil suggests that the modern compact male cone of Ephedra was indeed derived from a once loosely-arranged shoot system, and the male reproductive unit originated from a once elongated axillary male shoot. This new fossil species thus provides a transitional link from the hypothetical ancestral shoot system to the modern compact morphology. Changes of habitat from closed humid forests to open dry deserts and shifts of the pollination syndrome may have acted as the driving forces behind this morphological evolution.

Cenozoic plant relicts are those groups that were once widespread in the Northern Hemisphere but are now restricted to some small isolated areas as a result of drastic climatic changes. They are good proxies to study how plants respond to climatic changes since their modern climatic requirements are known. Herein we look at the modern distribution of 65 palaeoendemic genera in China and compare it with the Chinese climatic pattern, in order to find a link between the plant distribution and climate. Central China and Taiwan Island are shown to be diversity centres of Cenozoic relict genera, consistent with the fact that these two regions have a shorter dry season with comparatively humid autumn and spring in China. Species distribution models indicate that the precipitation parameters are the most important variables to explain the distribution of relict genera. The Cenozoic wide-scale distribution of relict plants in the Northern Hemisphere is therefore considered to be linked to the widespread humid climate at that time and the subsequent contraction of their distributional ranges was probably caused by the drying trend along with global cooling.

Generic delimitation in the Beilschmiedia group of the Lauraceae remains ambiguous because flowering specimens of a few genera with confined distribution are poorly represented in herbaria, and a few floral characters important for taxonomy are still poorly known. Syndiclis is sporadically distributed in southwestern China, and is represented in the herbaria by only a few flowering specimens. We conducted field investigations to collect floral materials of four species and observed structures and ontogeny of the tiny flowers using both light microscopy (LM) and scanning electron microscopy (SEM). The results show that the genus Syndiclis possesses flowers with huge variation in both merosity and organ number. Flowers of the genus are dimerous, trimerous, or tetramerous, or have mixed merosity with monomerous and dimerous, or dimerous and trimerous, or trimerous and tetramerous whorls. The number of staminodes ranges from two to eight, depending on floral merosity, and on how many stamens of the third androecial whorl are reduced to staminodes. The staminodes of the fourth androecial whorl are comparable to the staminodes in Potameia, but the staminodes of the third androecial whorl of Syndiclis are relatively larger than the staminodes in Potameia. They are erect or curved inwards, covering the ovary. The anthers are usually two-locular, but rarely one-locular or three-locular. Each stamen of the third androecial whorl bears two conspicuous and enlarged glands at the base. The lability of floral merosity and organ number of Syndiclis may have been caused by changes of pollination system and loss of special selective pressures that are present in most Lauraceous plants with fixed floral organ number. This study furthers our understanding of variation and evolution of a few important characters of the Beilschmiedia group and provides essential data for a revised generic classification of the group.

Background Understanding the relationship between human evolution and environmental changes is the key to lifting the veil on human origin. The hypothesis that environmental changes triggered the divergence of humans from apes (ca. 9.3–6.5 million years ago, Ma) has been poorly tested because of limited continuous environmental data from fossil localities. Lufengpithecus (12.5-6.0 Ma) found on the southeastern margin of the Tibetan Plateau (SEMTP) across the ape–human split provides a good chance for testing this hypothesis. Results Here, we reconstructed the habitats of L . keiyuanensis (12.5–11.6 Ma) with comprehensive vegetation, climate, and potential food web data by palaeobotanical evidence, together with other multidisciplinary data and partly tested the environment-driven hypothesis by revealing the living conditions of Lufengpithecus . Conclusion A detailed comparison of hominoids on different continents reveals their behaviour and fate divergence across the ape–human split against the background of global climate change, i.e., the stable living conditions of SEMTP not only provided a so-called ‘refuge’ for arboreal Lufengpithecus but also acted as a ‘double-edged sword’, preventing their further evolution while vegetation shifts in East Africa probably stimulated the emergence of human bipedalism, and the intense climatic changes in Europe possibly prevented those hominoids from surviving that time interval. Our findings provide interesting insight into the environmental impacts on the behavioural evolution of hominoids.

Floral characters are important for the systematics of the Lauraceae. However, structure and development of the flowers remain poorly known in the family. In this study, we observed the variation and early development of flowers of Beilschmiedia appendiculata, which belongs to the Cryptocarya clade of the family. The results indicate that the shoot apical meristems (SAMs) of the floral buds are enlarged and become a platform for the programmed initiation of the floral organs; floral organs develop basically in an acropetal pattern; phyllotaxis is whorled, initiation of floral primordia within a whorl is asynchronous; floral merosity is extremely variable, for example, dimerous, trimerous, tetramerous, dimerous plus trimerous, and trimerous plus tetramerous. In addition, this species has lost the innermost staminal whorl and glands are not closely associated with stamens of the third staminal whorl, which is unusual in the family Lauraceae. Our new observations broaden our knowledge of the variation of floral structure in Beilschmiedia and pose a fundamental question regarding the ecology underlying the lability of floral organs in B. appendiculata. Floral merosity of Beilschmiedia appendiculata is extremely variable, for example, dimerous, trimerous, tetramerous, dimerous plus trimerous, and trimerous plus tetramerous. This species has lost the innermost staminal whorl, and glands are not closely associated with stamens of the third staminal whorl, which is unusual in the family Lauraceae.

Both Trapa L. and the extinct Hemitrapa Miki are aquatic plants in the family Lythraceae, with abundant fossil records in Eurasia and North America in the Cenozoic. However, documented materials are mainly based on fruit and pollen grains without reliable leaf fossils. Here, we report fossil leaves, fruit, and roots of Trapa and fruit of Hemitrapa from the late Eocene of Weinan, the Weihe Basin of central China. The fossil leaves are identified as a new species, Trapa natanifolia Z. C. Han et H. Jia sp. nov., which represents the earliest known record of a Trapa leaf fossil. It is remarkably similar to extant species of Trapa, mostly due to the unique inflated petiole structures found in both of them. While displaying prominent intergeneric differences, the incomplete fossil fruits are assigned to Trapa sp. indet. and Hemitrapa sp. indet. The former is the earliest fossil fruit record of Trapa, and the latter represents the earliest fossil record of Hemitrapa found in Asia. These new fossil discoveries suggest that the divergence of Trapa and Hemitrapa occurred at least by the late Eocene. It is believed that modern Trapa most likely originated in China. Furthermore, this unexpected aquatic plant fossil assemblage indicates that central China was warm and humid, with freshwater ponds or lakes, in the late Eocene and not as arid as previously thought.

A new species of Ephedraceae, i.e. Ephedra chengiae sp. nov., is described and illustrated here. This new species is similar to E. rituensis Y.Yang ＆ al. and E. intermedia Schrenk ＆ C.A.Mey. in the erect habit with prominent woody stems, elongated twigs with many nodes, and the long micropylar tube. However, it differs from E. rituensis by the synangia being prominently stipitate (vs. sessile), the female cone having fewer bract pairs (3-4 vs. 4-5), its glossy seeds, and from E. intermedia by the prominently stipitate synangia (vs. sessile or nearly so), the female cone having fewer bract pairs (3-4 vs. 2-5), the glossy seeds (vs. seeds not glossy), and the micropylar tube being more or less straight (vs. twisted). Ephedra chengiae var. spinosa var. nov. differs from var. chengiae in its cushion-like habit and the spinose twigs.