Zhuo Feng | Yunnan University (original) (raw)
Papers by Zhuo Feng
Beetles are the most diverse group of macroscopic organisms since the mid-Mesozoic. Much of beetl... more Beetles are the most diverse group of macroscopic organisms since the mid-Mesozoic. Much of beetle speciosity is attributable to myriad life habits, particularly diverse-feeding strategies involving interactions with plant substrates, such as wood. However, the life habits and early evolution of wood-boring beetles remain shrouded in mystery from a limited fossil record. Here we report new material from the upper Permian (Changhsingian Stage, ca. 254–252 million-years ago) of China documenting a microcosm of ecological associations involving a polyphagan wood-borer consuming cambial and wood tissues of the conifer Ningxiaites specialis. This earliest evidence for a component community of several trophically interacting taxa is frozen in time by exceptional preservation. The combination of an entry tunnel through bark, a cambium mother gallery, and up to 11 eggs placed in lateral niches—from which emerge multi-instar larval tunnels that consume cambium, wood and bark—is ecologically convergent with Early Cretaceous bark-beetle borings 120 million-years later.
eds.), Cold Spring Harbor Perspectives. Sinnott E.W. (1921). The relation between body size and o... more eds.), Cold Spring Harbor Perspectives. Sinnott E.W. (1921). The relation between body size and organ size in plants.
A permineralised gymnosperm wood, Xenoxylon yunnanensis Feng sp. nov., is described from the Midd... more A permineralised gymnosperm wood, Xenoxylon yunnanensis Feng sp. nov., is described from the Middle Jurassic Shaximiao Formation in Huize County, Yunnan Province, Southwest China. The pycnoxylic wood consists of thick-walled tracheids and thin-walled rays. It is characterised by uniseriate, contiguous, compressed bordered pits on the radial walls of tracheids, and one large simple pit in each cross-field. Growth rings exhibit narrow late-wood. The mean sensitivity of analysis of 25 growth rings is 0.2, suggesting that a climate with abundant rainfall and weak seasonality could have prevailed in Yunnan, at least locally, during the Middle Jurassic. The outer portion of the wood is largely decayed, and shows poorly preserved cells lacking details. Decayed tracheids displaying various features, including removal of middle lamellae, separations of secondary walls, presence of thickened corners and appositions, are recognised as cell reactions to fungal activity. Irregularly distributed micro-cavities are formed by complete decomposition of tracheids and rays in the wood. Abundant fungal remains occurring in the wood generally consist of multiple branched hyphae. These fungal hyphae are either confined to individual cell lumens or extend through adjacent cells. Although the probable reproductive structure and typical clamp connection are very rarely observed with few septate hyphae, the affinities of these fungal hy-phae are somewhat obscure. Nevertheless, our study sheds light on the palaeoecology of Middle Jurassic terrestrial ecosystems of Southwest China.
Review of Palaeobontay and Palynolgoy, 2017
Bark is an important functional structure in woody plants. However, fossil tree axes are commonly... more Bark is an important functional structure in woody plants. However, fossil tree axes are commonly decorticated. The development of bark during the evolutionary history of fossil plants thus remains poorly understood. Here, we describe exceptionally well-preserved extraxylary tissues of the Lopingian (Late Permian) conifer Ningxiaites specialis Feng, including vascular cambium and bark, from the Sunjiagou Formation (Changhsingian) of northern China. The vascular cambium bears one or two layers of cambial cells. The bark comprises secondary phloem and periderm. The secondary phloem consists of rays, axial parenchyma and sieve cells. The rays of the secondary phloem are uniseriate and continuous from the rays of the xylem. They are more frequently present in the inner zone of the secondary phloem. Axial parenchyma cells are vertically aligned and appear more regularly distributed in the outer zone of the secondary phloem. Elliptical or subcircular sieve areas are placed on the radial walls of the sieve cells. The periderm located outside the secondary phloem is composed of imbricate flattened cork cells. The cork cells show suberised cell walls and are generally filled with dark contents. Remains of the secondary phloem present between layers of periderm indicate the formation of rhytidome-type bark. This is the first detailed report of the bark anatomy of a conifer from the upper Palaeozoic of Cathaysia, and shed light on the early diversity of bark structure during the evolutionary history of conifers.
Scientific reports, 2015
Leaf traces are important structures in higher plants that connect leaves and the stem vascular s... more Leaf traces are important structures in higher plants that connect leaves and the stem vascular system. The anatomy and emission pattern of leaf traces are well studied in extant vascular plants, but remain poorly understood in fossil lineages. We quantitatively analysed the leaf traces in the late Permian conifer Ningxiaites specialis from Northwest China based on serial sections through pith, primary and secondary xylems. A complete leaf traces emission pattern of a conifer is presented for the first time from the late Palaeozoic. Three to five monarch leaf traces are grouped in clusters, arranged in a helical phyllotaxis. The leaf traces in each cluster can be divided into upper, middle and lower portions, and initiate at the pith periphery and cross the wood horizontally. The upper leaf trace increases its diameter during the first growth increment and then diminishes completely, which indicates leaf abscission at the end of the first year. The middle trace immediately bifurcate...
An Early Permian (290.6 ±1.8 Ma) fossil assemblage has been discovered from the Leukersdorf Forma... more An Early Permian (290.6 ±1.8 Ma) fossil assemblage has been discovered from the Leukersdorf Formation in the Chemnitz Basin, Germany. The first systematic excavation of the Chemnitz Petrified Forest (2008-2011) provided more than 1,800 petrifactions and cast fossils from different volcaniclastic units and their sedimentary basement. The autochthonous fossil deposit originated from volcanic eruptions and preserved the most complete Permian forest ecosystem known to date. 53 trunk bases, still standing upright in their place of growth and rooting in the underlying paleosol, characterise this fossil lagerstätte as a significant T 0 –assemblage and gives insights into a spatially restricted lowland environment. The latter sheltered a dense hygrophilous vegetation of of ferns, sphenophytes, and gymnosperms as well as a diverse fauna of vertebrates, arthropods and gastropods. The comprehensive data-set of 3D coordinates gathered for every fossil find resulted in a special database and a 3...
Oribatid mites (Acari: Oribatida) are very diverse and important detritivorous and fungivorous mi... more Oribatid mites (Acari: Oribatida) are very diverse and important detritivorous and fungivorous micro-arthropods
in modern forest ecosystems. Although the fossil record of oribatid mites can be traced to the Early Devonian, the
paleoecology of oribatid mites during the deep geological past remains poorly understood. Remarkably good
preservation of tunnel networks in a permineralized coniferwood specimen is described fromthe Early Permian
of Germany. This fossil provides evidence for four aspects of oribatid mite feeding habits. First, there is preferred
consumption of the more indurated tissues from growth-ring cycles. Second, tracheids were targeted for
consumption. Third, feeding on tissues resulted in fecal pellet accumulations at the bottoms of tunnels. And
fourth, the absence of feeding on ambient decomposing fungi such as necroses and rots, but rather the processing
of pristine plant tissues, indicate the presence of a self-contained, microorganismic gut biota. These rather
specialized feeding habits allowed oribatid mites a prominent role in the decomposition of digestively refractory
plant tissues in Early Permian ecosystems.
Bulletin of Geosciences, 2014
A Middle Pennsylvanian tuff bed (the Bělka bed) in the roof of the Lower Radnice Coal bears T 0 p... more A Middle Pennsylvanian tuff bed (the Bělka bed) in the roof of the Lower Radnice Coal bears T 0 peat-forming vegetation preserved in growth position. This vegetation has been studied in detail at the 12 hectares large Ovčín coal deposit in the southern part of the Radnice Basin. Documentation of the fossil record in six excavations and that previously collected in the former opencast mine allowed for a detailed reconstruction of the local peat-forming lepidodendrid-cordaitalean forest structured into well-developed stories. It consists of about 33 species, which colonized the occasionally flooded planar peat swamp precursor of the Lower Radnice Coal. The canopy story of this vegetation was dominated by Lepidodendron (Paralycopodites) simile, L. lycopodioides, Lepidophloios acerosus and Cordaites borassifolius. They formed a relatively dense canopy, locally interrupted with significant gaps allowing development of a rich groundcover that together with liana-like plants represents the most diverse part of the forest. A less diverse understory composed of calamites, medullosan pteridosperms and Psaronius tree ferns displays a patchy distribution pattern presumably related to density of the canopy. The minimal area that sufficiently represents the pattern of this forest phytocoenosis is estimated to be about 200 m 2 , although lower stories are well represented even within much smaller areas of about 60 m 2 . Slight heterogeneity in the population density of dominant taxa (Cordaites vs. lepidodendrid lycopsids) was documented across the Ovčín coal deposit. The fossil record of the Bělka tuff bed also indicates that the coal-forest colonizing the peat swamp prior the generation of forest killed by volcanic ash fall, was destroyed, presumably due to long-lasting flooding and thus suggests that catastrophic events were probably a relatively common part of the evolution of peat-forming Pennsylvanian successions. • Key words: Pennsylvanian, T 0 plant assemblage, coal forests, volcanic ash beds, Radnice Basin.
Remarkably good preserved and coprolite-filled tunnel works are presented in permineralised conif... more Remarkably good preserved and coprolite-filled tunnel works are presented in permineralised conifer wood from the lower Permian Rotliegend (Asselian) of Thuringia. In comparison to several fossil examples we refer this feeding habit to oribatid mites (Acari: Oribatida), a group of very diverse and important detritivorous and fungivorous micro-arthropods found in nearly all modern terrestrial ecosystems from the tropics to the Antarctic continent. Moreover, the fossil record of detritivorous organisms and their feeding patterns is diverse and can be traced back to the late Silurian, when animal life has been accompanied the greening of the terrestrial realm. However, the palaeoecology of oribatid mites in deep geological time still remains poorly understood. The fossil evidence presented here reveals four interesting aspects of feeding patterns: 1) a preferred consumption of more lignified elements of the woody tissues along growth-ring cycles, 2) targeted tracheids for consumption a...
Bulletin of Geosciences
AMiddle Pennsylvanian tuff bed (the Bělka bed) in the roof of the Lower Radnice Coal bears T0 pea... more AMiddle Pennsylvanian tuff bed (the Bělka bed) in the roof of the Lower Radnice Coal bears T0 peat-forming vegetation preserved in growth position. This vegetation has been studied in detail at the 12 hectares large Ovčín coal deposit in the southern part of the Radnice Basin. Documentation of the fossil record in six excavations and that previously collected in the former opencast mine allowed for a detailed reconstruction of the local peat-forming lepidodendrid-cordaitalean forest structured into well-developed stories. It consists of about 33 species, which colonized the occasionally flooded planar peat swamp precursor of the Lower Radnice Coal. The canopy story of this vegetation was dominated by Lepidodendron (Paralycopodites) simile, L. lycopodioides, Lepidophloios acerosus and Cordaites borassifolius. They formed a relatively dense canopy, locally interrupted with significant gaps allowing development of a rich groundcover that together with liana-like plants represents the m...
Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of... more Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Araucariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for conservation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.
Taxon, 2014
Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of... more Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Araucariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for conservation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.
Chinese Science Bulletin, 2014
ABSTRACT Noeggerathiales are an extinct group of spore-bearing plants of uncertain systematic pos... more ABSTRACT Noeggerathiales are an extinct group of spore-bearing plants of uncertain systematic position that are known from Carboniferous and Permian age Euramerican and Cathaysian floras that occurred in present-day Europe, North America, and East Asia. The order Noeggerathiales includes over 50 species of more than 20 fossil genera, but their paleoecology is not well understood yet. Previously this group had been found only in extrabasinal floras or those inhabiting clastic wetlands. Noeggerathiales have never been recorded in coal ball floras. Thus, it is up to now uncertain whether this group has contributed to the formation of coal. Recent investigations of an Early Permian peat-forming flora of the Taiyuan Formation near Wuda, Inner Mongolia, which was preserved in a volcanic ash fall has provided evidence that noeggerathialean plants not only existed in the peat-forming vegetation but could even be the dominant group in some areas of the coal swamp. The Noeggerathiales in this particular peat-forming forest include Tingia unita, Paratingia wudensis, and a new species of Paratingia. Exceptionally well-preserved specimens indicate that these noeggerathialean plants are small trees with a canopy of compound leaves and strobili near the top of an unbranched (monocaulous) stem.
Leaf skeletonization represents a distinctive form of insect feeding behavior. It commonly occurs... more Leaf skeletonization represents a distinctive form of insect feeding behavior. It commonly occurs in angiosperm leaves after their initial appearance during the Early Cretaceous. This type of feeding behavior rarely has been documented in pre-Mesozoic fossils. We describe the earliest evidence of insect-skeletonized leaves of Dictyophyllum nathorstii Zeiller, affi liated with the extant fern family Dipteridaceae in the Late Triassic Yipinglang fl ora from southwestern China. The skeletonization generally is located adjacent to the pinna rachilla of the distal free portion of the leaf. In the skeletonized area, the interveinal tissue is completely removed, exposing the pinna rachilla, pinnule midveins, and lateral veins. Most nonvascular tissue has been removed between the vascular bundles, the latter forming polygonal meshes of varying size. Our report of insect-mediated skeletonization of fern leaves from southwestern China fi lls a spatiotemporal gap in the published data on the paleogeographical distribution and stratigraphic occurrence of plant-arthropod associations, and indicates an antagonistic relationship between a fern host and its insect herbivore.
A new bipinnate fertile pinna, Sterzelitheca chemnitzensis, bearing alternate synangia, is descri... more A new bipinnate fertile pinna, Sterzelitheca chemnitzensis, bearing alternate synangia, is described from the Chemnitz Petrified Forest, Germany. The specimen occurs in the basal volcanic ash of the Zeisigwald Tuff Horizon, Leukersdorf Formation, Lower Permian. Because it is partially embedded in the tuffaceous matrix, X-ray microcomputer tomography was employed to investigate the complete morphology without mechanical preparation of the hand specimen. The pinna is 66 mm long and branched once at least, the ultimate pinnae alternately positioned on the penultimate axis at angles of 45-55°. Stalked synangia are bell-like, borne alternately on both the terminal portion of the penultimate axis and the ultimate axes at angles of 25-60°. The smooth walled stalk is 3-7 mm long, 1-1.5 mm wide. Individual synangia are up to 6.5 mm in diameter and 10 mm long, and bear 12-14 elongated sporangia. Tubular sporangia are thin walled, circular in transverse section, arranged at the rim of the circular synangial pad around a central hollow. The unique preservational mould of the studied specimen is neither a permineralisation nor a compression-impression. It is three-dimensionally preserved, but lacks any organic remains. We provide the first detailed three-dimensional features of a probable medullosan male reproductive organ from the Chemnitz Fossil Lagerstätte. The relatively simple structure of the specimen offers a better understanding of the Palaeozoic seed ferns.
Aims Our knowledge of tylosis formation is mainly based on observations of extant plants; however... more Aims Our knowledge of tylosis formation is mainly based on observations of extant plants; however, its developmental and functional significance are less well understood in fossil plants. This study, for the first time, describes a complete tylosis formation in a fossil woody conifer and discusses its ecophysiological implications. † Methods The permineralized stem of Shenoxylon mirabile was collected from the upper Permian (Changhsingian) Sunjiagou Formation of Shitanjing coalfield, northern China. Samples from different portions of the stem were prepared by using the standard thin-sectioning technique and studied in transmitted light. † Key Results The outgrowth of ray parenchyma cells protruded into adjacent tracheids through pits initially forming small pyriform or balloon-shaped structures, which became globular or slightly elongated when they reached their maximum size. The tracheid luminae were gradually occluded by densely spaced tyloses. The host tracheids are arranged in distinct concentric zones representing different growth phases of tylosis formation within a single growth ring. † Conclusions The extensive development of tyloses from the innermost heartwood (metaxylem) tracheids to the outermost sapwood tracheids suggests that the plant was highly vulnerable and reacted strongly to environmental stress. Based on the evidence available, the tyloses were probably not produced in response to wound reaction or pathogenic infection, since evidence of wood traumatic events or fungal invasion are not recognizable. Rather, they may represent an ecophysiological response to the constant environmental stimuli.
and sharing with colleagues.
A novel coniferous tree trunk, Plyophyllioxylon hulstaiense gen. nov. et sp. nov., is described f... more A novel coniferous tree trunk, Plyophyllioxylon hulstaiense gen. nov. et sp. nov., is described from the Lower Shihhotse Formation (Guadalupian, Permian) of the Hulstai coalfield, in the Inner Mongolia Autonomous Region of northern China. The decorticated tree trunk is permineralized and is characterized by broad eustele and well-developed pycnoxylic secondary xylem. The parenchymatous pith is up to 30 mm in diameter, with the central portion septated by diaphragms and the perimedullary cells continuous. The primary xylem is endarch; tracheids from protoxylem to metaxylem possess helical, annular, and scalariform/reticulate thickenings. The monarch leaf traces initiate from the pith margin and are arranged according to a helical phyllotaxy of 3/24 or 4/24. Tracheids in the secondary xylem have uni-to biseriate araucarioid pits; cross field pits are cupressoid. Ray cells are parenchymatous, with smooth walls, uni-to biseriate. Vertically aligned or isolated axial xylem parenchyma is interpreted as an evolutionary adaptation to the increasingly arid local environment. Crystallized or spheroidal storage substances contained in the axial parenchyma also suggest that the local environment had become unstable by at least the Guadalupian. Distinctive coprolites are preserved within the pith chambers, spheroidal or ovoid shaped, 20-50 mm in diameter, interpreted as a new type of feeding behavior, likely by a detritivorous arthropod.
An exquisitely well-preserved woody stem from northern China provides additional evidence for the... more An exquisitely well-preserved woody stem from northern China provides additional evidence for the biodiversity of latest Permian of the Cathaysian flora. The specimen of Ningxiaites specialis gen. nov. et sp. nov. was collected from the Sunjiagou Formation in the Shitanjing coalfield, Ningxia Hui Autonomous Region. The permineralised plant is featured by a eustelic vascular system, thick pycnoxylic woody cylinder, and prominent helically arranged clusters of leaf traces. The circular parenchymatous pith is surrounded by more than 30 endarch primary xylem strands and numerous distinctive leaf traces. Leaf traces initiate from the pith margin singly, bifurcate immediately or remain as a single bundle when crossing the wood cylinder. The wood is especially characterised by the development of inflated cells and pitted tangential (terminal/end) wall of ray cells. The new plant is tentatively assigned to the conifers although it shows few similarities with ginkgophytes, which might indicate the early conifer and ginkgophyte woods could be very similar to each other. Spheroidal and oval coprolites preserved in its pith and adjacent xylem is interpreted as having an oribatid mite origin.
Beetles are the most diverse group of macroscopic organisms since the mid-Mesozoic. Much of beetl... more Beetles are the most diverse group of macroscopic organisms since the mid-Mesozoic. Much of beetle speciosity is attributable to myriad life habits, particularly diverse-feeding strategies involving interactions with plant substrates, such as wood. However, the life habits and early evolution of wood-boring beetles remain shrouded in mystery from a limited fossil record. Here we report new material from the upper Permian (Changhsingian Stage, ca. 254–252 million-years ago) of China documenting a microcosm of ecological associations involving a polyphagan wood-borer consuming cambial and wood tissues of the conifer Ningxiaites specialis. This earliest evidence for a component community of several trophically interacting taxa is frozen in time by exceptional preservation. The combination of an entry tunnel through bark, a cambium mother gallery, and up to 11 eggs placed in lateral niches—from which emerge multi-instar larval tunnels that consume cambium, wood and bark—is ecologically convergent with Early Cretaceous bark-beetle borings 120 million-years later.
eds.), Cold Spring Harbor Perspectives. Sinnott E.W. (1921). The relation between body size and o... more eds.), Cold Spring Harbor Perspectives. Sinnott E.W. (1921). The relation between body size and organ size in plants.
A permineralised gymnosperm wood, Xenoxylon yunnanensis Feng sp. nov., is described from the Midd... more A permineralised gymnosperm wood, Xenoxylon yunnanensis Feng sp. nov., is described from the Middle Jurassic Shaximiao Formation in Huize County, Yunnan Province, Southwest China. The pycnoxylic wood consists of thick-walled tracheids and thin-walled rays. It is characterised by uniseriate, contiguous, compressed bordered pits on the radial walls of tracheids, and one large simple pit in each cross-field. Growth rings exhibit narrow late-wood. The mean sensitivity of analysis of 25 growth rings is 0.2, suggesting that a climate with abundant rainfall and weak seasonality could have prevailed in Yunnan, at least locally, during the Middle Jurassic. The outer portion of the wood is largely decayed, and shows poorly preserved cells lacking details. Decayed tracheids displaying various features, including removal of middle lamellae, separations of secondary walls, presence of thickened corners and appositions, are recognised as cell reactions to fungal activity. Irregularly distributed micro-cavities are formed by complete decomposition of tracheids and rays in the wood. Abundant fungal remains occurring in the wood generally consist of multiple branched hyphae. These fungal hyphae are either confined to individual cell lumens or extend through adjacent cells. Although the probable reproductive structure and typical clamp connection are very rarely observed with few septate hyphae, the affinities of these fungal hy-phae are somewhat obscure. Nevertheless, our study sheds light on the palaeoecology of Middle Jurassic terrestrial ecosystems of Southwest China.
Review of Palaeobontay and Palynolgoy, 2017
Bark is an important functional structure in woody plants. However, fossil tree axes are commonly... more Bark is an important functional structure in woody plants. However, fossil tree axes are commonly decorticated. The development of bark during the evolutionary history of fossil plants thus remains poorly understood. Here, we describe exceptionally well-preserved extraxylary tissues of the Lopingian (Late Permian) conifer Ningxiaites specialis Feng, including vascular cambium and bark, from the Sunjiagou Formation (Changhsingian) of northern China. The vascular cambium bears one or two layers of cambial cells. The bark comprises secondary phloem and periderm. The secondary phloem consists of rays, axial parenchyma and sieve cells. The rays of the secondary phloem are uniseriate and continuous from the rays of the xylem. They are more frequently present in the inner zone of the secondary phloem. Axial parenchyma cells are vertically aligned and appear more regularly distributed in the outer zone of the secondary phloem. Elliptical or subcircular sieve areas are placed on the radial walls of the sieve cells. The periderm located outside the secondary phloem is composed of imbricate flattened cork cells. The cork cells show suberised cell walls and are generally filled with dark contents. Remains of the secondary phloem present between layers of periderm indicate the formation of rhytidome-type bark. This is the first detailed report of the bark anatomy of a conifer from the upper Palaeozoic of Cathaysia, and shed light on the early diversity of bark structure during the evolutionary history of conifers.
Scientific reports, 2015
Leaf traces are important structures in higher plants that connect leaves and the stem vascular s... more Leaf traces are important structures in higher plants that connect leaves and the stem vascular system. The anatomy and emission pattern of leaf traces are well studied in extant vascular plants, but remain poorly understood in fossil lineages. We quantitatively analysed the leaf traces in the late Permian conifer Ningxiaites specialis from Northwest China based on serial sections through pith, primary and secondary xylems. A complete leaf traces emission pattern of a conifer is presented for the first time from the late Palaeozoic. Three to five monarch leaf traces are grouped in clusters, arranged in a helical phyllotaxis. The leaf traces in each cluster can be divided into upper, middle and lower portions, and initiate at the pith periphery and cross the wood horizontally. The upper leaf trace increases its diameter during the first growth increment and then diminishes completely, which indicates leaf abscission at the end of the first year. The middle trace immediately bifurcate...
An Early Permian (290.6 ±1.8 Ma) fossil assemblage has been discovered from the Leukersdorf Forma... more An Early Permian (290.6 ±1.8 Ma) fossil assemblage has been discovered from the Leukersdorf Formation in the Chemnitz Basin, Germany. The first systematic excavation of the Chemnitz Petrified Forest (2008-2011) provided more than 1,800 petrifactions and cast fossils from different volcaniclastic units and their sedimentary basement. The autochthonous fossil deposit originated from volcanic eruptions and preserved the most complete Permian forest ecosystem known to date. 53 trunk bases, still standing upright in their place of growth and rooting in the underlying paleosol, characterise this fossil lagerstätte as a significant T 0 –assemblage and gives insights into a spatially restricted lowland environment. The latter sheltered a dense hygrophilous vegetation of of ferns, sphenophytes, and gymnosperms as well as a diverse fauna of vertebrates, arthropods and gastropods. The comprehensive data-set of 3D coordinates gathered for every fossil find resulted in a special database and a 3...
Oribatid mites (Acari: Oribatida) are very diverse and important detritivorous and fungivorous mi... more Oribatid mites (Acari: Oribatida) are very diverse and important detritivorous and fungivorous micro-arthropods
in modern forest ecosystems. Although the fossil record of oribatid mites can be traced to the Early Devonian, the
paleoecology of oribatid mites during the deep geological past remains poorly understood. Remarkably good
preservation of tunnel networks in a permineralized coniferwood specimen is described fromthe Early Permian
of Germany. This fossil provides evidence for four aspects of oribatid mite feeding habits. First, there is preferred
consumption of the more indurated tissues from growth-ring cycles. Second, tracheids were targeted for
consumption. Third, feeding on tissues resulted in fecal pellet accumulations at the bottoms of tunnels. And
fourth, the absence of feeding on ambient decomposing fungi such as necroses and rots, but rather the processing
of pristine plant tissues, indicate the presence of a self-contained, microorganismic gut biota. These rather
specialized feeding habits allowed oribatid mites a prominent role in the decomposition of digestively refractory
plant tissues in Early Permian ecosystems.
Bulletin of Geosciences, 2014
A Middle Pennsylvanian tuff bed (the Bělka bed) in the roof of the Lower Radnice Coal bears T 0 p... more A Middle Pennsylvanian tuff bed (the Bělka bed) in the roof of the Lower Radnice Coal bears T 0 peat-forming vegetation preserved in growth position. This vegetation has been studied in detail at the 12 hectares large Ovčín coal deposit in the southern part of the Radnice Basin. Documentation of the fossil record in six excavations and that previously collected in the former opencast mine allowed for a detailed reconstruction of the local peat-forming lepidodendrid-cordaitalean forest structured into well-developed stories. It consists of about 33 species, which colonized the occasionally flooded planar peat swamp precursor of the Lower Radnice Coal. The canopy story of this vegetation was dominated by Lepidodendron (Paralycopodites) simile, L. lycopodioides, Lepidophloios acerosus and Cordaites borassifolius. They formed a relatively dense canopy, locally interrupted with significant gaps allowing development of a rich groundcover that together with liana-like plants represents the most diverse part of the forest. A less diverse understory composed of calamites, medullosan pteridosperms and Psaronius tree ferns displays a patchy distribution pattern presumably related to density of the canopy. The minimal area that sufficiently represents the pattern of this forest phytocoenosis is estimated to be about 200 m 2 , although lower stories are well represented even within much smaller areas of about 60 m 2 . Slight heterogeneity in the population density of dominant taxa (Cordaites vs. lepidodendrid lycopsids) was documented across the Ovčín coal deposit. The fossil record of the Bělka tuff bed also indicates that the coal-forest colonizing the peat swamp prior the generation of forest killed by volcanic ash fall, was destroyed, presumably due to long-lasting flooding and thus suggests that catastrophic events were probably a relatively common part of the evolution of peat-forming Pennsylvanian successions. • Key words: Pennsylvanian, T 0 plant assemblage, coal forests, volcanic ash beds, Radnice Basin.
Remarkably good preserved and coprolite-filled tunnel works are presented in permineralised conif... more Remarkably good preserved and coprolite-filled tunnel works are presented in permineralised conifer wood from the lower Permian Rotliegend (Asselian) of Thuringia. In comparison to several fossil examples we refer this feeding habit to oribatid mites (Acari: Oribatida), a group of very diverse and important detritivorous and fungivorous micro-arthropods found in nearly all modern terrestrial ecosystems from the tropics to the Antarctic continent. Moreover, the fossil record of detritivorous organisms and their feeding patterns is diverse and can be traced back to the late Silurian, when animal life has been accompanied the greening of the terrestrial realm. However, the palaeoecology of oribatid mites in deep geological time still remains poorly understood. The fossil evidence presented here reveals four interesting aspects of feeding patterns: 1) a preferred consumption of more lignified elements of the woody tissues along growth-ring cycles, 2) targeted tracheids for consumption a...
Bulletin of Geosciences
AMiddle Pennsylvanian tuff bed (the Bělka bed) in the roof of the Lower Radnice Coal bears T0 pea... more AMiddle Pennsylvanian tuff bed (the Bělka bed) in the roof of the Lower Radnice Coal bears T0 peat-forming vegetation preserved in growth position. This vegetation has been studied in detail at the 12 hectares large Ovčín coal deposit in the southern part of the Radnice Basin. Documentation of the fossil record in six excavations and that previously collected in the former opencast mine allowed for a detailed reconstruction of the local peat-forming lepidodendrid-cordaitalean forest structured into well-developed stories. It consists of about 33 species, which colonized the occasionally flooded planar peat swamp precursor of the Lower Radnice Coal. The canopy story of this vegetation was dominated by Lepidodendron (Paralycopodites) simile, L. lycopodioides, Lepidophloios acerosus and Cordaites borassifolius. They formed a relatively dense canopy, locally interrupted with significant gaps allowing development of a rich groundcover that together with liana-like plants represents the m...
Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of... more Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Araucariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for conservation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.
Taxon, 2014
Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of... more Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Araucariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for conservation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.
Chinese Science Bulletin, 2014
ABSTRACT Noeggerathiales are an extinct group of spore-bearing plants of uncertain systematic pos... more ABSTRACT Noeggerathiales are an extinct group of spore-bearing plants of uncertain systematic position that are known from Carboniferous and Permian age Euramerican and Cathaysian floras that occurred in present-day Europe, North America, and East Asia. The order Noeggerathiales includes over 50 species of more than 20 fossil genera, but their paleoecology is not well understood yet. Previously this group had been found only in extrabasinal floras or those inhabiting clastic wetlands. Noeggerathiales have never been recorded in coal ball floras. Thus, it is up to now uncertain whether this group has contributed to the formation of coal. Recent investigations of an Early Permian peat-forming flora of the Taiyuan Formation near Wuda, Inner Mongolia, which was preserved in a volcanic ash fall has provided evidence that noeggerathialean plants not only existed in the peat-forming vegetation but could even be the dominant group in some areas of the coal swamp. The Noeggerathiales in this particular peat-forming forest include Tingia unita, Paratingia wudensis, and a new species of Paratingia. Exceptionally well-preserved specimens indicate that these noeggerathialean plants are small trees with a canopy of compound leaves and strobili near the top of an unbranched (monocaulous) stem.
Leaf skeletonization represents a distinctive form of insect feeding behavior. It commonly occurs... more Leaf skeletonization represents a distinctive form of insect feeding behavior. It commonly occurs in angiosperm leaves after their initial appearance during the Early Cretaceous. This type of feeding behavior rarely has been documented in pre-Mesozoic fossils. We describe the earliest evidence of insect-skeletonized leaves of Dictyophyllum nathorstii Zeiller, affi liated with the extant fern family Dipteridaceae in the Late Triassic Yipinglang fl ora from southwestern China. The skeletonization generally is located adjacent to the pinna rachilla of the distal free portion of the leaf. In the skeletonized area, the interveinal tissue is completely removed, exposing the pinna rachilla, pinnule midveins, and lateral veins. Most nonvascular tissue has been removed between the vascular bundles, the latter forming polygonal meshes of varying size. Our report of insect-mediated skeletonization of fern leaves from southwestern China fi lls a spatiotemporal gap in the published data on the paleogeographical distribution and stratigraphic occurrence of plant-arthropod associations, and indicates an antagonistic relationship between a fern host and its insect herbivore.
A new bipinnate fertile pinna, Sterzelitheca chemnitzensis, bearing alternate synangia, is descri... more A new bipinnate fertile pinna, Sterzelitheca chemnitzensis, bearing alternate synangia, is described from the Chemnitz Petrified Forest, Germany. The specimen occurs in the basal volcanic ash of the Zeisigwald Tuff Horizon, Leukersdorf Formation, Lower Permian. Because it is partially embedded in the tuffaceous matrix, X-ray microcomputer tomography was employed to investigate the complete morphology without mechanical preparation of the hand specimen. The pinna is 66 mm long and branched once at least, the ultimate pinnae alternately positioned on the penultimate axis at angles of 45-55°. Stalked synangia are bell-like, borne alternately on both the terminal portion of the penultimate axis and the ultimate axes at angles of 25-60°. The smooth walled stalk is 3-7 mm long, 1-1.5 mm wide. Individual synangia are up to 6.5 mm in diameter and 10 mm long, and bear 12-14 elongated sporangia. Tubular sporangia are thin walled, circular in transverse section, arranged at the rim of the circular synangial pad around a central hollow. The unique preservational mould of the studied specimen is neither a permineralisation nor a compression-impression. It is three-dimensionally preserved, but lacks any organic remains. We provide the first detailed three-dimensional features of a probable medullosan male reproductive organ from the Chemnitz Fossil Lagerstätte. The relatively simple structure of the specimen offers a better understanding of the Palaeozoic seed ferns.
Aims Our knowledge of tylosis formation is mainly based on observations of extant plants; however... more Aims Our knowledge of tylosis formation is mainly based on observations of extant plants; however, its developmental and functional significance are less well understood in fossil plants. This study, for the first time, describes a complete tylosis formation in a fossil woody conifer and discusses its ecophysiological implications. † Methods The permineralized stem of Shenoxylon mirabile was collected from the upper Permian (Changhsingian) Sunjiagou Formation of Shitanjing coalfield, northern China. Samples from different portions of the stem were prepared by using the standard thin-sectioning technique and studied in transmitted light. † Key Results The outgrowth of ray parenchyma cells protruded into adjacent tracheids through pits initially forming small pyriform or balloon-shaped structures, which became globular or slightly elongated when they reached their maximum size. The tracheid luminae were gradually occluded by densely spaced tyloses. The host tracheids are arranged in distinct concentric zones representing different growth phases of tylosis formation within a single growth ring. † Conclusions The extensive development of tyloses from the innermost heartwood (metaxylem) tracheids to the outermost sapwood tracheids suggests that the plant was highly vulnerable and reacted strongly to environmental stress. Based on the evidence available, the tyloses were probably not produced in response to wound reaction or pathogenic infection, since evidence of wood traumatic events or fungal invasion are not recognizable. Rather, they may represent an ecophysiological response to the constant environmental stimuli.
and sharing with colleagues.
A novel coniferous tree trunk, Plyophyllioxylon hulstaiense gen. nov. et sp. nov., is described f... more A novel coniferous tree trunk, Plyophyllioxylon hulstaiense gen. nov. et sp. nov., is described from the Lower Shihhotse Formation (Guadalupian, Permian) of the Hulstai coalfield, in the Inner Mongolia Autonomous Region of northern China. The decorticated tree trunk is permineralized and is characterized by broad eustele and well-developed pycnoxylic secondary xylem. The parenchymatous pith is up to 30 mm in diameter, with the central portion septated by diaphragms and the perimedullary cells continuous. The primary xylem is endarch; tracheids from protoxylem to metaxylem possess helical, annular, and scalariform/reticulate thickenings. The monarch leaf traces initiate from the pith margin and are arranged according to a helical phyllotaxy of 3/24 or 4/24. Tracheids in the secondary xylem have uni-to biseriate araucarioid pits; cross field pits are cupressoid. Ray cells are parenchymatous, with smooth walls, uni-to biseriate. Vertically aligned or isolated axial xylem parenchyma is interpreted as an evolutionary adaptation to the increasingly arid local environment. Crystallized or spheroidal storage substances contained in the axial parenchyma also suggest that the local environment had become unstable by at least the Guadalupian. Distinctive coprolites are preserved within the pith chambers, spheroidal or ovoid shaped, 20-50 mm in diameter, interpreted as a new type of feeding behavior, likely by a detritivorous arthropod.
An exquisitely well-preserved woody stem from northern China provides additional evidence for the... more An exquisitely well-preserved woody stem from northern China provides additional evidence for the biodiversity of latest Permian of the Cathaysian flora. The specimen of Ningxiaites specialis gen. nov. et sp. nov. was collected from the Sunjiagou Formation in the Shitanjing coalfield, Ningxia Hui Autonomous Region. The permineralised plant is featured by a eustelic vascular system, thick pycnoxylic woody cylinder, and prominent helically arranged clusters of leaf traces. The circular parenchymatous pith is surrounded by more than 30 endarch primary xylem strands and numerous distinctive leaf traces. Leaf traces initiate from the pith margin singly, bifurcate immediately or remain as a single bundle when crossing the wood cylinder. The wood is especially characterised by the development of inflated cells and pitted tangential (terminal/end) wall of ray cells. The new plant is tentatively assigned to the conifers although it shows few similarities with ginkgophytes, which might indicate the early conifer and ginkgophyte woods could be very similar to each other. Spheroidal and oval coprolites preserved in its pith and adjacent xylem is interpreted as having an oribatid mite origin.