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Simple Summary: In 2019, Late Devonian Xinhang forest was reported from Anhui Province, China. It represents the earliest forest in Asia and China, and was regarded as monospecific with numerous small trees of the lycopsid. Recently, we found some other plants from the forest and now erect a new fern-like plant named Xinhangia. It is small with height of tens of centimeters, and usually has two orders of branches in alternate and sometimes triseriate pattern. Spines densely occur on the main axes and primary branches. Its leaf-like organs are very simple and dichotomize into recurved tips. Fertile organs are similar to the "leaves" but terminated in elongate and paired sporangia. Both the "leaves" and fertile organs are alternately arranged on secondary branches. In anatomy, the primary xylem is "8"-shaped and is surrounded by secondary xylem. With simple characters, Xinhangia represents a morphologically primitive plant and is of uncertain affinity at class or order level. As a component of Xinhang forest, Xinhangia will help understand the growth habit and habitat of fern-like plants, as well as the structure and ecology of ancient forests in the future. Palaeozoic fern-like plants show great diversity in their morphology and/or anatomy. Within this group, a novel taxon, Xinhangia spina gen. et sp. nov., is now reported from the Upper Devonian (Famennian) Wutong Formation of Anhui Province, China. The primary and secondary branches are borne alternately and sometimes in a triseriate pattern. Spines are evident on the main axes or stems and on the primary branches. Vegetative ultimate appendages with recurved tips are alternate, usually dichotomous 1–2 times, and sometimes as an aphlebia located at the base of primary or secondary branches. Fertile ultimate appendages are alternate, usually dichotomous 1–2 times, and terminate in elongated and paired sporangia. The stele has a clepsydroid-like primary xylem with each end bearing a protoxylem strand. The secondary xylem surrounding the primary xylem illustrates uniseriate rays. With rare divisions in both the vegetative and fertile ultimate appendages, Xinhangia represents a morphologically primitive plant. It is of uncertain affinity at the class or order level. The stelar architecture suggests that the clepsydroid stele may not be emphasized in discussing the relationship among fern-like plants such as rhacophytaleans. [ABSTRACT FROM AUTHOR]

Tree lycopsids prospered in the Late Devonian and constituted a major part of the Late Paleozoic forest ecosystem that deeply impacted the Earth's climate. However, the fertile organs of these early tree lycopsids display low morphological disparity, which has hampered further knowledge about their ecological habit. Here, we report Omprelostrobus gigas gen. et sp. nov. from the Upper Devonian (Famennian) Wutong Formation at Changxing, Zhejiang, China. The collection includes aerial axes, strobili and associated roots. The strobili are the largest among coeval lycopsids to our knowledge, and are divided into proximal and distal portions by dimorphic sporophylls with differentiated laminae and probable strong photosynthetic capacity. The associated but not attached roots displaying multiple isotomous branches lack rootlets and typical rootlet scars. The varied strobili sizes of early tree lycopsids were relatively independent of their body plan, but the large strobili could suggest increased reproductive investment to overcome the disadvantages of the disturbed flooded habitat. A new species of Late Devonian fossil lycopsid with large strobili and differentiated sporophylls provides insight into reproductive investment of early tree lycopsids. [ABSTRACT FROM AUTHOR]

The earliest ovules in the Late Devonian (Famennian) are surrounded by a cupule that is involved in both protection and pollination, and generally have free integumentary lobes. Here we report a new taxon from the Famennian of China, Guazia dongzhiensis gen. et sp. nov. The terminally borne ovule is apparently acupulate (without cupule) and has four radially arranged wing-like integumentary lobes that are extensively fused, and folded lengthwise and inwards. Guazia provides evidence that not all Devonian seeds possess a cupule and it increases their diversity in integumentary lobes. This genus also suggests that the integuments develop new functions, probably including wind dispersal at the expense of the cupules. [ABSTRACT FROM AUTHOR]

Kunia venusta gen. et sp. nov. is reported from the late Middle Devonian (Givetian) Haikou Formation near Kunming City, Yunnan Province, China. This plant has three orders of naked axes that divide pseudomonopodially. The second- and third-order axes occur in a helix. Fertile appendages are distantly spaced and helically inserted to the third-order axis; they comprise equally dichotomous branches terminated by two clusters of paired and fusiform sporangia. Sterile appendages are dichotomous and distally recurved. A comparison is made with the basal euphyllophytes including the trimerophytes, cladoxylopsids, zygopterids, stauropterids, and some relevant genera of uncertain affinity. The new plant resembles them in dichotomous appendages with terminal elongated sporangia, but differs mainly in the three orders of pseudomonopodial axes bearing helical laterals. It is thus placed in the Euphyllophytina as incertae sedis. It is suggested that an evolutionary divergence in the branching pattern and appendage morphology might have occurred in the Middle Devonian euphyllophytes, that is, maintaining three dimensions versus yielding more or less planation. [ABSTRACT FROM AUTHOR]

Archaeopteris macilenta is one of the most widespread plants in the Late Devonian. Based on fossils from the Frasnian Huangjiadeng Formation, Yichang District of Hubei Province, for the first time we study in detail the anatomy of this progymnosperm plant in South China. Ultimate axes are protostelic with three xylem sympodia and lack secondary tissue. Penultimate axes are eustelic, bearing eight sympodia and a thin band of secondary xylem. Radially symmetrical sympodia of mesarch primary xylem produce traces of appendages in a spiral arrangement. Archaeopteris macilenta and A. halliana ( A. roemeriana) are dominant in the Frasnian and Famennian, respectively. Comparisons with these two species from other tectonic plates indicate consistent stelar architectures. Global spread, continuous occurrence, and identical anatomy during the Late Devonian indicate that Archaeopteris survived the Frasnian-Famennian extinction event. In this time, endemic genera and cosmopolitan taxa, including Archaeopteris, suggest the palaeogeographic isolation of South China and certain associations with other plates. [ABSTRACT FROM AUTHOR]

Abstract: The propensity of coal to spontaneous combustion demonstrates the inherent character of the oxidation capacity at normal temperature. Currently, based on simulating spontaneous combustion of coal using adiabatic oxidation and temperature-programmed experiment, many overseas countries test characteristic parameters of spontaneous combustion of coal, such as SHT, HR, R70, CPT, high-temperature activation energy, and so on. Oxygen adsorption method is used to test the absorbed oxygen at 30 °C in China. According to the deficiency of the present research using partial stage parameters to demonstrate the whole process, Oxidation Kinetics which reflects the entire dynamic process is put forward, through testing the concentration of oxygen in the outlet of sample vessel at 70 °C and CPT later. With results repeated well and simple manipulation, the method can reflect the self-heating character very well and thus has a vital significance for the prevention and control of the mine fire. [Copyright &y& Elsevier]

A new vascular plant, Hsüa deflexa sp. nov., is documented from the Lower Devonian ((upper) Pragian-lower Emsian) Xujiachong Formation, near Xujiachong village, Qujing District, eastern Yunnan, South China. In three dimensions, the branching system comprises a robust creeping main axis and comparatively slender erect lateral axes inserted oppositely or alternately. The lateral axes depart at right angles from the main axis. Towards the apex, the main axis is perhaps erect with the lateral axes attached at smaller angles. The lateral axes dichotomize equally one to three times in different planes and decrease in diameter and length acropetally. They bear sparse and irregular tiny spines. Apices of a pair of distal lateral axes curve in opposite directions and each terminates in a rounded to reniform sporangium. The sporangium dehisces into two equal valves along an indistinct convex marginal thickening. The xylem is possibly centrarch. This plant fits Hsüa in branching pattern, sporangial characters and xylem maturation.Hsüa deflexa sp. nov. differs mainly from the type speciesH. robusta in the presence of axial spines, perpendicular extension of lateral axes from the main axis and curving of distal lateral axes. Based on the possibly cen-trarch xylem and terminal sporangium, this plant relates to the rhyniophytes (sensu Banks, 1968). In view of the equal sporangial valves with marginal thickenings it resembles the zosterophyllophytes (sensu Banks, 1968).Hsüa is now treated asincertae sedis. [ABSTRACT FROM AUTHOR]

The study of a Late Devonian arborescent lycopsid, Sublepidodendron songziense Chen 1977, from the Hsiehchingssu (Xiejingsi) Formation of Hubei Province and the Wutung (Wutong) Formation of Anhui Province, PR China, provides new insight into its holistic architecture and taxonomic affinity. The study allows several interrelated organ species to be integrated into a conceptual whole-plant species, Sublepidodendron songziense Chen emend. Wang Q., Hao, Wang D.-M., Wang Y. et Thomas Denk. The plant consists of a monocaulous trunk growing from a stigmarian rhizomorph, the trunk bearing biseriate, sub-opposite to possibly alternate lateral branches that expand by means of isotomous to slightly anisotomous dichotomies, forming an excurrent canopy. Lateral branches bear terminal Lepidostrobus-like strobili. These strobili are dimorphic, implying separate mega- and microsporangiate strobili considered with the associated organ assemblage, including Triletes-type megaspores, Lepidocarpopsis-like sporophylls, and Lepidophloios-like cauline anatomy. Moreover, lateral branches are caducous, and ulodendroid scars mark the attachment sites of former branches onto the trunk. The plant diagnostically possesses spirally arranged, small, vertically elongated leaf cushions, which have false leaf scars. The presence of ligule cannot be excluded definitely. The characteristics of leaf cushions show considerable variation corresponding to different taphonomic processes, preservational modes and ontogenetic stages so that this plant megafossil has been classified in various ways previously. Based on organic connection and cauline anatomy, a reconstruction of the whole-plant species is tentatively given. We compare this whole-plant species to the type species S. mirabile (Nathorst) Hirmer, and revise Sublepidodendron (Nathorst) Hirmer 1927, suggesting that the genus and its own family Sublepidodendraceae sensu Kra¨usel et Weyland 1949 should be separated from the order Protolepidodendrales sensu Pichi-Sermolli 1958 and referred to the order Isoe¨tales sensu lato and the suborder Dichostrobiles sensu DiMichele et Bateman 1996. Present Ulodendron specimens are the earliest record in the Late Palaeozoic strata, demonstrating that the pseudomonopodial branching architectural form in the arboresent lycopsids had evolved by the Late Devonian (Famennian). Such a woody trunk together with lateral branches (or cauline peduncles), separate mega- and microsporangiate strobili, and rootlet-bearing rhizomorph epitomize the major structural units (or architectural modules) of a true arborescent lycopsid, and S. songziense appears to be the oldest arborescent lycopsid showing an apparently centralized rhizomorph. We suggest that phylogenetically more advanced arborescent lycopsids did not precipitately occur in the Carboniferous, rather they had already evolved by the Late Devonian (Famennian). The widespread genus Sublepidodendron (Nathorst) Hirmer 1927 emend., especially abundant in China, among the Late Devonian–Early Carboniferous floras may represent one of the progenitors of the phylogenetically advanced arborescent lycopsids. [Copyright &y& Elsevier]

Abstract: Pauthecophyton gracile gen. et sp. nov. is described from the Lower Devonian (Pragian) Posongchong Formation near Zhichang Village of Wenshan District, southeastern Yunnan, China. This plant consists of pseudomonopodially and dichotomously branched main axes and lateral branches. Some laterals are pseudomonopodially divided producing three to four times dichotomously branched systems terminating in sporangia; other branches are isotomously divided six to eight times terminating in sporangia. Fusiform sporangia are grouped as fertile units; each unit, generally with two, three or four sporangia, is subtended by a branch which generally divides once or twice. Sporangia lacking twisting have a longitudinal dehiscence and contain similarly sized spores with laevigate and folded exine. Pauthecophyton probably occupies a basal position within the euphyllophytes, as one of the earliest divergent clades. It is more similar to the genus Psilophyton Dawson than to others in branching, as well as sporangial shape, terminal position and longitudinal dehiscence; these similarities, more likely to be plesiomorphic characters of the euphyllophytes, indicate that they both belong to the “trimerophyte grade”. The character of twisted sporangia in trimerophytes and the phytogeographic isolation of euphyllophytes in South China are discussed. [Copyright &y& Elsevier]

Abstract: A new plant, Dibracophyton acrovatum gen. et sp. nov., is described from the Lower Devonian (Pragian) Posongchong Formation of Wenshan District, southeastern Yunnan, China. The plant has creeping axes from which arise vegetative and fertile axes. The vegetative axes helically bear lateral dichotomous appendages with curved or round tips. The fertile axes possess terminal strobili with numerous fertile units arranged in irregular helices. Each fertile unit consists of a stalked long-elliptical sporangium, with dehiscence into two equal valves, and two discrete long-ovate bracts covering sporangium from above–below directions. A new genus and species is thus established based on these characters and is temporarily regarded as incertae sedis of Tracheophyta, although it perhaps closes to the barinophytes in affinity. Detailed comparisons with other plants having a similar architecture, i.e., sporangia closely associated with modified vegetative structures, are made. The discovery of D. acrovatum further enriches the composition of the Posongchong flora and demonstrates great morphological disparity of the Early Devonian vascular plants. [Copyright &y& Elsevier]

Abstract: A new species of early vascular plant, Adoketophyton parvulum sp. nov., is described from the Lower Devonian (Pragian) Posongchong Formation of Yunnan, China. The plant is composed of main axes, lateral vegetative branches and isotomous or anisotomous fertile axes. The vegetative axes branch isotomously or pseudomonopodially in three dimensions, with some laterals ending in terminal circinately coiled tips. K-shaped branching and tubercles are preserved. Terminal strobili consist of four vertical rows of fertile units, arranged in opposite and decussate pairs. Each fertile unit comprises a fan-shaped sporophyll and a sporangium attached adaxially by a short stalk at the base of the sporophyll. The strobili and fertile units (sporophylls and associated sporangia) of this new species are much smaller than those of the type species, Adoketophyton subverticillatum, and the ratio of heights of sporangia to sporophyll laminae in the two species shows a large discrepancy. The affinity and evolution of Adoketophyton are discussed. The various leaf-like appendages in plants reported from the Early Devonian of South China are considered a phenomenon of convergent evolution. [Copyright &y& Elsevier]

Purpose: To investigate the efficacy and safety of interventional embolization in the treatment of frontal arteriovenous malformation (AVM)., Methods: A retrospective study was used to analyze 9 patients with frontal AVM who were treated in Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine. The patients were treated with interventional embolization under the guidance of DSA. The scope of lesions was observed through DSA, and the injection dose of sclerosing agent was predicted so that the drug could be injected into the lesion cavity. The efficacy, adverse reactions and complications of all patients were observed and analyzed., Results: Among the 9 patients, there were 7 males(77.8%) and 2 females(22.2%), aged from 1.5-20 years old. Local swelling or mass was the main reported symptom(66.7%). The blood supply arteries of the cases involved in this study included superficial temporal artery and ophthalmic artery. All patients received interventional embolization treatment under general anesthesia, a total of 19 times (each patient received 1-6 times, average 2.1 times/person), and the average single dose of absolute ethanol was 9.0 mL. A total of 80 coils (4.2 coils/time on average) were used for 5 times (80 coils/19 times) with absolute ethanol embolization. In addition, bleomycin was used 3 times, pingyangmycin was used 2 times, and 3% polydocanol was used 1 time to assist embolization. Among the 9 cases included in this study, 4 cases were cured, 3 cases were basically cured, 2 cases were improved, and the effective rate of treatment was 100%. No local or systemic complications were reported in all patients., Conclusions: In the treatment of frontal arteriovenous malformation, correct diagnosis according to clinical and imaging manifestations, and interventional embolization with anhydrous ethanol according to DSA angiography results can reduce trauma, improve symptoms, control lesions, and obtain relatively satisfactory treatment results. This scheme is safe and effective.

Background: Guangdedendron micrum is the Late Devonian tree lycopsid that made up Xinhang fossil forest in Anhui, China, showing the earliest stigmarian rooting system. Based on new specimens of this lycopsid, the roots bearing rootlets, terminal parts of stems, vegetative leaves and monosporangiate strobili containing megaspores are researched in detail., Results: The roots with four robust rhizomorphs are largely expanded and approach the size of those of the Late Carboniferous giant tree lycopsids in swampy forests. The rootlets along rhizomorphic axis leave oval to circular scars after abscission. Narrow-fusiform leaf cushions display a leaf scar, vascular bundle and ligule pit. Cylindrical megasporangiate strobili are borne singly, in pairs, or occasionally once-dichotomized. Of each megasporophyll, the pedicel consists of a keel and possibly undeveloped alations, and the long-triangular lamina presents a heel. Megasporangium is sessile and contains multiple Lagenicula megaspores with distinct spines and a large gula., Conclusions: G. micrum displays large terminal monosporangiate strobili probably adapted to turbulent condition, and its megasporophylls together with multiple Lagenicula-type megaspores hint a possible primitive evolutionary status. These characteristics provide new insights into the evolution of fertile traits of early lycopsids., (© 2022. The Author(s).)

Background: Previous studies have discussed the special structural adaptations of Late Palaeozoic lycopsids, for example, the dispersal potential of reproductive organs. Based on materials from the Upper Devonian Wutong Formation in Changxing County, Zhejiang Province, China, we now analyze the morphometric and perform some calculation to evaluate the dispersal of sporophyll units of lycopsids., Results: The fossil sporophyll units are divided into two types in view of obvious difference in shape and we name two new (form) species for them. We also analyze the falling process and give the calculation method of dispersal distance., Conclusions: The fossil sporophyll units show relatively poor potential of wind dispersal compared with modern samaras, and show potential adaptation to the turbulent environment., (© 2021. The Author(s).)

The earliest known ovules in the Late Devonian (Famennian) are borne terminally on fertile branches and are typically enclosed in a cupule. Among these ovules are some that have terete integumentary lobes with little or no fusion. Here, we report a new taxon, Latisemenia longshania, from the Famennian of South China, which bears cupulate ovules that are terminal as well as opposite on the fertile axis. Each ovule has four broad integumentary lobes, which are extensively fused to each other and also to the nucellus. The cupule is uniovulate, and the five flattened cupule segments of each terminal ovule are elongate cuneate and shorter than the ovule. Associated but not attached pinnules are laminate and Sphenopteris-like, with an entire or lobate margin. Latisemenia is the earliest known plant with ovules borne on the side of the fertile axis and may foreshadow the diverse ovule arrangements found among younger seed plant lineages that emerge in the Carboniferous. Following the telome theory, Latisemenia demonstrates derived features in both ovules and cupules, and the shape and fusion of integumentary lobes suggest effective pollination and protection to the nucellus. Along with other recent discoveries from China, Latisemenia extends the palaeogeographic range of the earliest seed plants., (© 2015 The Author(s).)

Background and Aims: With the exception of angiosperms, the main euphyllophyte lineages (i.e. ferns sensu lato, progymnosperms and gymnosperms) had evolved laminate leaves by the Late Devonian. The evolution of laminate leaves, however, remains unclear for early-diverging ferns, largely represented by fern-like plants. This study presents a novel fern-like taxon with pinnules, which provides new insights into the early evolution of laminate leaves in early-diverging ferns., Methods: Macrofossil specimens were collected from the Upper Devonian (Famennian) Wutong Formation of Anhui and Jiangsu Provinces, South China. A standard degagement technique was employed to uncover compressed plant portions within the rock matrix., Key Results: A new fern-like taxon, SHOUGANGIA BELLA GEN ET SP NOV: , is described and represents an early-diverging fern with highly derived features. It has a partially creeping stem with adventitious roots only on one side, upright primary and secondary branches arranged in helices, tertiary branches borne alternately or (sub)oppositely, laminate and usually lobed leaves with divergent veins, and complex fertile organs terminating tertiary branches and possessing multiple divisions and numerous terminal sporangia., Conclusions: Shougangia bella provides unequivocal fossil evidence for laminate leaves in early-diverging ferns. It suggests that fern-like plants, along with other euphyllophyte lineages, had independently evolved megaphylls by the Late Devonian, possibly in response to a significant decline in atmospheric CO2 concentration. Among fern-like plants, planate ultimate appendages are homologous with laminate pinnules, and in the evolution of megaphylls, fertile organs tend to become complex., (© The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)