Zhuo Feng

Forests constitute the dominant terrestrial ecosystems and play a critical role in global carbon cycling. However, the changing structure and function of forests through geological time remain poorly understood due to the scarcity of in situ fossil forests preserving detailed and physiologically important anatomical characters. On the basis of 78 in situ permineralized conifer stumps in the Yiwu Jurassic Forest of Xinjiang, China, we quantitatively reconstruct the forest using paleobotanical observations and ecological analyses. We found that this fossil forest has a random tree distribution with an average density of 126 trees per hectare, showing limited postestablishment competitive thinning; its estimated canopy height ranged from 10.47 to 43.95 meters, stand-level biomass was 276,192 to 386,946 kilograms per hectare, and a notable net primary productivity of 21.11 to 31.9 t/hm ² ·a, which is three times higher than that of modern temperate conifer forests. Elevated temperature and atmospheric p CO ₂ in the Middle Jurassic probably contributed to this high productivity. Our study indicates that tree density, canopy height, and biomass equivalent to modern forests had already emerged by the Middle Jurassic and that forests were functioning as major terrestrial carbon sinks.

Permochoristidae is a megadiverse mecopteran group that has mainly been reported from Russia and Australia, whereas records from China remain scarce. In this report, two new species of Mesochorista are described and illustrated from the Guadalupian Yinping Formation, Eastern China. Mesochorista tillyardi Lian and Huang, sp. nov. is characterized by the forewing covered with dense oval spots, and Sc₁ closely approximal to R₁ and connected by a short sc-r crossvein. Mesochorista yinpingensis Lian and Huang, sp. nov. is characterized by the forewing covered with dense irregularly colored patches, Sc₁ devoid of expanded area, and M with only five branches. Based on a detailed discussion of the type species and other co-occurring species of Mesochorista and Permochorista, in light of the new insights into Sc₃, we support that Permochorista is a junior synonym of Mesochorista.

The Permian–Triassic (P-Tr) transition (~252 Ma) witnessed Earth’s most severe biocrisis, which has long been linked to Siberian Traps volcanism and associated environmental upheaval. Major perturbation of the global carbon (C) and sulfur (S) cycles is mainly inferred from marine δ ¹³ C and δ ³⁴ S records, whereas few existing terrestrial records link δ ³⁴ S fluctuations to widespread dispersal and fallout of volcanogenic sulfate aerosols. Mounting evidence, however, reveals that the collapse of P-Tr terrestrial ecosystems was diachronous, questioning a hypothesized globally synchronous common forcing. Here, we present records of pyritic multiple-S isotopes (δ ³⁴ S _py and Δ ³³ S) and bulk organic δ ¹³ C for a paleotropical peatland drill core (HK-1) from Southwest China. The δ ³⁴ S _py variations define three distinct phases with a notable decline in δ ³⁴ S _py across the P-Tr transition, suggesting substantially elevated terrestrial sulfate influx coincident with major carbon cycle perturbation. Notably, overall small positive Δ ³³ S values (+0.01 to +0.12‰) rule out a dominant role for stratospheric sulfates. Collectively, the observed changes in δ ¹³ C _org , δ ³⁴ S _py , and Δ ³³ S support catastrophic collapse of the Cathaysian Flora leading to intensified weathering and sulfate release. This inferred event, slightly after the P-Tr marine extinction, postdates by several 100-ky terrestrial floral collapse and perturbation of the C–S cycles documented in the high-latitude Sydney Basin. Cross-latitudinal diachroneity of terrestrial ecosystem collapse and consequent C–S perturbation challenges the hypothesis of a single, global volcanic driver. Rather, regional deforestation and its cascading effects overprinted on the global perturbations of biogeochemical cycles emerge here as critical factors shaping Earth’s largest recorded crisis.

Abundant Triassic spinicaudatans from China have been commonly assigned to the genus Euestheria Depéret & Mazeran. However, recent SEM-based studies have revealed that many of them do not belong to euestherids, as evidenced by their distinctive micro-ornamentations, revealed by scanning electron microscopy (SEM). In this study, we describe two spinicaudatan species, Polygrapta yipinglangensis comb. nov. and P. dazuensis comb. nov., which were previously identified as members of Euestheria from the Upper Triassic Ganhaizi and Xujiahe formations in south-western China. The carapace ornamentations of these species exhibit fine polygonal reticulations in the upper parts, which gradually transform to linear arrangements and radial lirae at the ventral regions. Based on these features, they are classified into Polygrapta Novojilov. Although the two species exhibit morphological similarities, they can be distinguished by variations in reticulation size and the width of linear arrangements in their marginal areas.

A new species of Orthophlebiidae, Orthophlebia lini Lian & Huang, sp. nov., is described and illustrated from the Middle Jurassic Yan’an Formation of Yan’an City, north China. The species is erected based on a specimen preserving both a forewing and a hindwing, and a paratype preserving only a hindwing. These specimens demonstrate variability in the relative lengths of Rs1+2 and Rs3+4 even within the same individual, confirming that previous taxonomic systems relying heavily on these features may be flawed. This new species represents the first mecopteran fossil species from the Yan’an Formation and increases our understanding of the species richness of Orthophlebiidae during the Jurassic.

A list of all known fossil wood taxa recorded from the Cretaceous, up to December of 2024, is given. The list contains 57 genera and 317 species of gymnospermous wood described from 48 countries across seven continents. 39 genera and 165 species were reported from Asia, 28 genera and 67 species from Europe, 33 genera and 48 species from Africa, 20 genera and 48 species from North America, 13 genera and 35 species from South America, 4 genera and 4 species from Australia and 5 genera and 12 species from Antarctica. 54 genera and 171 species were documented from the Lower Cretaceous, and 26 genera and 76 species from the Upper Cretaceous. Systematically, 1 genus and 2 species belong to Cycadales, 1 monotypic genus belongs to Bennettitales, 2 genera and 3 species belong to Ginkgoales, 52 genera and 306 species are of Coniferales, and 1 genus and 3 species are incertae sedis.

This paper reports the first in-situ fossil evidence for silica biomineralisation in Permian plants. The discovery reinforces the significant role that land plants have played in influencing the evolution of Earth systems in deep time.

Interactions between arthropods and plants have been documented extensively in late Paleozoic trees and ground cover plants, but they have rarely been recorded in late Paleozoic climbers. In this study, we present the second example of coprolites preserved within the plant tissue from the early Permian fossil Lagerstätte Wuda Tuff Flora. The host axis is identified as a phyllophore of the climbing fern Hansopteris uncinatus by the combined evidence of anatomy, morphology, and associated plants. Unlike the first coprolites, which were suggested to be produced by oribatid mites, the culprit of the studied coprolites was likely a myriapod or beetle, indicated by their slightly larger size and the boring behaviour. Furthermore, anomalous parenchymatous cells, sclerenchymatous cells, and metaxylem tracheids have been observed surrounding the tunnel, suggesting responses to traumatic stimulus caused by arthropod damage. This discovery provides an informative example of arthropod herbivory on late Paleozoic climbers and sheds light on how the host plant responded during the early stage of injury.