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Nothotsuga is a monotypic genus of Pinaceae endemic to southern China today. Molecular data indicate that Nothotsuga split from Tsuga during the Palaeogene with the earliest fossils from the upper ...

Premise of research. Cyclocarya Iljinskaya (Juglandaceae) is a genus with a single living species that is endemic to central and south China. The genus has an abundant North American and Eurasian fossil record from the Paleocene to the Pliocene, documenting its spread across Europe to western Siberia during the Oligocene and its arrival in Japan by the Miocene. However, there have been no fossil occurrences of Cyclocarya near its modern distribution. In this study, we describe a new species of Cyclocarya from the upper Miocene Nanlin Formation in Lianghe County, western Yunnan Province, southwest China, and discuss its biogeographic implications.Methodology. We examined the fossil fruit using LM and SEM, and we compared its morphology with fruits of fossil Cyclocarya and extant Cyclocarya paliurus (Batalin) Iljinsk.Pivotal results. The fossil fruit of Cyclocarya simipaliurus sp. nov. consists of a small nutlet that is surrounded by a circular and flange-like wing. The nutlet is circular in plan view and o...

Abundant fossil records indicate that the genus Smilax L was widely distributed in North America and Europe during the Paleogene and thrived in the Miocene. However, since the early Pliocene, the fossil occurrence of Smilax has become very rare. In this study, we describe three leaf taxa of Smilax from the upper Pliocene of West Yunnan, Southwest China based on their leaf architecture and cuticle features. Smilax tengchongensis sp. nov. and Smilax cf. bracteata Presl differ from each other both in leaf shape and cuticle features. The leaves of Smilax sp. possess a different shape and venation but share similar cuticle features with those of S. tengchongensis sp. nov. The morphological diversity of our fossils indicates that a warm and humid climate with a multilayered structure existed in the Pliocene forests of West Yunnan. Moreover, recent molecular studies indicate that both New World and Old World species of Smilax exhibited an intercontinental disjunct distribution via the Beringia land bridge between East Asia and North America. However, this biogeographic disjunction is not well demonstrated by the fossil records as a result of inadequate paleobotanical data. (C) 2017 Elsevier B.V. All rights reserved.

Phylogenetic analyses indicate that the genus Podocarpus diverged around the Cretaceous/Paleogene boundary, and two monophyletic subgenera Podocarpus and Foliolatus had differentiated during the Paleogene. Most of described fossil remains were related to the subgenus Podocarpus, but those of the subgenus Foliolatus have not been well documented. Here, we described a new species of Podocarpus, P. yunnanensis sp. nov., and P. cf. forrestii from the lower Pliocene of western Yunnan, China based on a detailed comparisons of gross leaf morphology and cuticular structures between the studied fossils and extant Podocarpus. These two fossil taxa together with P. pliomacrophyllus H. Chen et J.Y. Wu from the same horizon, revealed a thriving of Podocarpus in western Yunnan during the Pliocene. For the subgenus Foliolatus, its early representatives might originate from Australasia and spread northward to northeastern India at least during the late Oligocene. The Neriifolius subclade within the subgenus is much older than the estimate of molecular clock studies, and the Indochinese subclade is probably derived from a rapid diversification driven by the continuous uplift of Hengduan Mountains (HDM) with the accompanying climate fluctuations since the late Miocene. Moreover, the thriving of Podocarpus in the Pliocene of western Yunnan reveals a warm and humid climate during that period. The Pleistocene glaciation and the geographic barriers posted by the HDM might contribute to the modern distribution of Podocarpus in South China and Indochina Peninsula.

A long shoot with needles and two immature seed cones, and some isolated organs of shoot, needles and seed cones from the late Miocene Shengxian Formation in Zhejiang Province, East China are described. A detailed comparison of the gross morphology and cuticle micromorphology of needles and seed cones with previously published Cenozoic fossils and related extant pine species reveals that the present fossils can be identified as a new species, Pinus premassoniana sp. nov., which has the closest affinity with extant Pinus massoniana. A pollen cone with copious bisaccate pollen grains from the same locality is identified as an indeterminate species of subgenus Pinus. The pollen grains show a verrucate external sculpture on the corpus and sacci and an alveolae internal structure in the sacci. The fossil needle cuticles and pollen cone of the genus Pinus from China are reported for the first time. The modern distribution indicates that P. premassoniana sp. nov. should also live under a warm and humid climate. Hitherto, there is no any reliable fossil record that has an affinity with the extant P. massoniana. The occurrence of the present fossils suggests that P. premassoniana has existed in East China since at least in the late Miocene.

Two types of fronds belonging to a new species, Drynaria dimorpha sp. nov., are described from the upper Pliocene Mangbang Formation in western Yunnan, southwestern China. The base frond is lobate and the lobes are incised up to 2/3 or more of the width. The foliage frond is preserved as individual fertile or sterile pinnae with serrated margin and constricted basal part. Circular son are arranged in one row on either side of the primary vein. In situ spores are monolete and planoconvex, elliptical in polar view and bean-shaped in equatorial view. A detailed morphological comparison suggests that none of the previously described drynarioid fossils and extant species is in accord with the present ferns. The discovery of this new fern indicates that a developed humus-collecting structure of Drynaria had existed and a species-level radiation of this genus had taken place at least by the late Pliocene. (C) 2012 Elsevier B.V. All rights reserved.

Smilax tiantaiensis sp. nov. is described from the Late Miocene Shenxian Formation in Zhejiang Province, East China based on five fossil leaves with fine venation and well preserved cuticles. The fossil leaves are characterized by an ovate shape, entire margin, mucronate apex, rounded base, five primary basal acrodromous veins with reticulate venation in between; leaves hypostomatic, anticlinal walls undulated and stomatal apparatus anomocytic. The fossils have been compared with extant and other fossil species hitherto described in this genus. Some fossil stromata, hyphae and spores identified as Callimothallus pertusus Dilcher (Microthyriaceae) were discovered on the both epidermides of S. tiantaiensis. The climbing habit of Smilax and the presence of the epiphyllous fungus of C. pertusus on the fossil leaves may indicate that the multistratified forest was growing under a humid climate during the Miocene in Zhejiang. (C) 2011 Elsevier B.V. All rights reserved.

Platycladus Spach is native to Central China, but its natural occurrences are very difficult to establish. According to molecular phylogenetic data, this genus might have originated since the Oligocene, but no fossil record has been reported. Here, we describe eight foliage branches from the upper Miocene in western Yunnan, Southwest China as a new species, P. yunnanensis sp. nov., which is characterized by foliage branches spread in flattened sprays, and leaves decussate, imbricate, scale-like and dimorphic. The leaves are amphistomatic, and the stomata are elliptical or oblong, haplocheilic, and monocyclic type. Based on a detailed comparison with the extant genera of Cupressaceae sensu lato, our fossils are classified into the genus Platycladus. The occurrence of P. yunnanensis sp. nov. indicates that this genus had a more southernly natural distribution in the late Miocene than at present. Molecular phylogeny and fossil records support a pre-Oligocene common ancestor for the genera Platycladus, Microbiota and Calocedrus. The separation of the three taxa was most likely caused by the arid belt across Central China during the Oligocene. In addition, the cooling down of the global temperature and the strengthening of Asian monsoon since the Miocene will further promote the migration of these genera.