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Early Cretaceous was a key period for the evolution of terrestrial ecosystems. In southeastern China, the late Early Cretaceous (Aptian–Albian) floras are relatively well known and characterized by diverse Cheirolepidiaceae, but the early Early Cretaceous floras in southeastern China are poorly known mainly because of the lack of plant fossils. Here we report petrified woods from a new early Early Cretaceous locality in Qingyuan, southern Zhejiang Province, southeastern China. The new fossil woods collected from the Xishantou Formation (earliest Berriasian, earliest Early Cretaceous) are assigned to Brachyoxylon zhejiangenseTian, Zhu, and Wang based on the anatomy of the secondary xylem. The new material of Brachyoxylon zhejiangensefrom Qingyuan lacks distinct growth rings or resin canals and has mixed type pitting on the radial walls of the tracheids, araucarioid cross-field pitting, and uniseriate rays. It is the earliest record of Brachyoxylonin southeastern China. Brachyoxylon zhejiangensehas been regarded as the wood of the extinct conifer family Cheirolepidiceae and grew in arid to semi-arid environments. Evidence also suggests Cheirolepidiaceae played an important role in the vegetation of southeastern China throughout the Early Cretaceous.

The nautiloid cephalopod Sinoceras chinense(Foord, 1888) was previously only known from the Upper Ordovician of Chinese blocks/terranes. Here, we document the first identification of S. chinensefrom the Kanchanaburi area, western Thailand. Upper part of the Tha Manao Formation containing S. chinenseis extremely similar both faunally and lithologically to the coeval Pagoda Formation of South China. This identification from Thailand not only extends the palaeobiogeographic distribution of S. chinense, but also supports the dynamic palaeogeographic reconstruction of the peri-Gondwana Chinese terranes and Sibumasu from Middle to Late Ordovician.

The end-Permian mass extinction (EPME) was known as the most severe biocrisis of the past 600 Ma. In order to explore the redox state of deep water environments, and the causal relationship between anoxia/euxinia and the EPME, this study selected the Penglaitan section in Guangxi, China, and measured the iron speciation and concentrations of trace elements and major elements. Several redox proxy approaches, including both iron speciation proxies and the excess fractions and enrichment factors of redox sensitive elements (RSEs), indicate that anoxia in the Penglaitan depositional environment was sporadic, with the majority of the section deposited under oxic conditions. This includes the interval immediately prior to and during the EPME; euxinia did not occur at the Penglaitan section around the EPME. Thus, anoxia was not the primary driver for the EPME at the Penglaitan section, and the accumulation of free H2S in the oceanic water-column could not have been the only proximal kill mechanism for the EPME at the Penglaitan section.

This study reports four species belonging to two genera of clathrodictyid stromatoporoids from the Sanqushan Formation (Katian, Upper Ordovician), Changshan County, Zhejiang Province, East China: Clathrodictyoncf. mammillatum(Schmidt), C. plicatumWebby and Banks, C. cf. microundulatumNestor and Labyrinthodictyon cascum(Webby and Morris). Of these, three species (C. cf. mammillatum, C. plicatumand L. cascum) show a wide range of skeletal variation, representing the variation from the normal skeletal phase to abnormal Ecclimadictyon-like crumpled skeletal phase, especially in the axial part of the columnar growth forms. It is uncertain whether the skeletal variation in early clathrodictyids was the result of environmental stress (such as abrupt sediment influxes that often cause growth interruptions of the stromatoporoids) or genetic inheritance. These characteristics suggest that this group had greater environmental tolerance than the earlier labechiids and increased ecological complexity during Late Ordovician by providing a stable, solid and elevated substrate for the other benthic organisms. This may imply that the labechiids and clathrodictyids are quite different groups, probably independently derived during the early evolution of stromatoporoids.