Angiosperm Wood Research Articles

Diversity of macrofungi in southeast Xizang 1. The wood-decay fungi

ABSTRACT A survey on the diversity of wood-decay fungi in southeast Xizang was carried out from 2019 to 2023. Based on morphology, ecology, biogeography, and molecular biology, 558 species, belonging to three classes, 15 orders, 57 families, and 177 genera, were identified. One new species, Epithele miscanthi, is described. Species composition analysis showed that there were fifteen dominant families with more than 10 species. These families include 459 species, accounting for 82.26% of the total species found. Thirty-three genera with five or more species are treated as dominant genera, and 325 species were included in these genera, accounting for 58.24% of the total species. Among these, 313 species (56.09%) occurred on angiosperm wood only, 168 species (30.11%) on gymnosperm wood only, 45 species (8.06%) on both angiosperm and gymnosperm wood, 17 species (3.05%) on monocotyledons only, and only one species, Hymenochaete rheicolor, grew on both monocotyledons and dicotyledons. The highest number of species, 266 (47.67%), were found on fallen trunks, followed by fallen branches, rotten wood, stumps, dead standing trees, living trees, and charred wood with 175, 123, 116, 82, 57, and 4 species, respectively. In addition, 456 species cause a white rot and 85 species cause a brown rot, accounting for 81.72% and 15.23% of our studied species, respectively. Statistics were also made on the rotting type and the number of edible or medicinal fungi.

Composition of Paleocene forests from Antarctica based on fossil wood

A new assemblage of fossil wood of Paleocene age from Seymour Island, Antarctic Peninsula, is described. Conifer species have been identified, belonging to the fossil genera Agathoxylon, Phyllocladoxylon, Protophyllocladoxylon, and Podocarpoxylon. Angiosperm fossil wood species are assigned to Nothofagoxylon, Caldcluvioxylon, and Myrceugenellites. New wood types have been described with possible affinity to Atherospermataceae and Asteraceae (daisy family). A newly identified fossil angiosperm species, Aextoxicoxylon jacksius, has been recorded from Antarctica for the first time. It shares traits with modern Aextoxicon punctatum and other Aextoxicoxylon wood from South America but is considered a separate species due to significant differences in vessel density, ray height, and frequency. This study indicates, in accordance with previous studies that conifers were the most common elements in the Paleocene Antarctic vegetation. In particular, Agathoxylon being the most dominant wood type. Nothofagoxylon was the most common angiosperm wood type. Overall the composition of the Antarctic Paleocene vegetation deduced from the presence of fossil wood resembles that of the modern warm to cool temperate forests of Tasmania, New Zealand and southern South America. Possible upland and lowland forest types have been identified, with the lowland forests likely most similar to the modern mixed cool temperate forests on South Island, New Zealand, and Tasmania. The upland forests were similar to the modern open canopy Araucaria-Nothofagus forests on the high Andes today.

Fungal composition associated with host tree identity mediates nutrient addition effects on wood microbial respiration.

Fungi are key decomposers of deadwood, but the impact of anthropogenic changes in nutrients and temperature on fungal community and its consequences for wood microbial respiration are not well understood. Here, we examined how nitrogen and phosphorus additions (field experiment) and warming (laboratory experiment) together influence fungal composition and microbial respiration from decomposing wood of angiosperms and gymnosperms in a subtropical forest. Nutrient additions significantly increased wood microbial respiration via fungal composition, but effects varied with nutrient types and taxonomic groups. Specifically, phosphorus addition significantly increased wood microbial respiration (65%) through decreased acid phosphatase activity and increased abundance of fast-decaying fungi (e.g., white rot), while nitrogen addition marginally increased it (30%). Phosphorus addition caused a greater increase in microbial respiration in gymnosperms than in angiosperms (83.3% vs. 46.9%), which was associated with an increase in Basidiomycota:Ascomycota operational taxonomic unit abundance in gymnosperms but a decrease in angiosperms. The temperature dependencies of microbial respiration were remarkably constant across nutrient levels, consistent with metabolic scaling theory hypotheses. This is because there was no significant interaction between temperature and wood phosphorus availability or fungal composition, or the interaction among the three factors. Our results highlight the key role of tree identity in regulating nutrient response of wood microbial respiration through controlling fungal composition. Given that the range of angiosperm species may expand under climate warming and forest management, our data suggest that expansion will decrease nutrient effects on forest carbon cycling in forests previously dominated by gymnosperm species.

Umbellaceae fam. nov. (Hymenochaetales, Basidiomycota) for Umbellus sinensis gen. et sp. nov. and Three New Combinations.

Hymenochaetales, belonging to Agaricomycetes, Basidiomycota, comprises most polypores and corticioid fungi and, also, a few agarics. The latest taxonomic framework accepts 14 families in this order. When further exploring species diversity of Hymenochaetales, two corticioid specimens collected from China producing cystidia with large umbrella-shaped crystalline heads attracted our attention. This kind of cystidia was reported only in three unsequenced species, viz. Tubulicrinis corneri, T. hamatus and T. umbraculus, which were accepted in Tubulicrinaceae, Hymenochaetales. The current multilocus-based phylogeny supports that the two Chinese specimens formed an independent lineage from Tubulicrinaceae as well as the additional 13 families and all sampled genera in Hymenochaetales. Therefore, a monotypic family, Umbellaceae, is newly described with the new genus Umbellus as the type genus to represent this lineage. The two Chinese specimens are newly described as U. sinensis, which differs from T. corneri, T. hamatus, and T. umbraculus in a combination of a smooth to grandinioid hymenophoral surface, not flattened, broadly ellipsoid basidiospores with a tiny apiculus, and growth on angiosperm wood. Due to the presence of the unique cystidia, the three species of Tubulicrinis, even though they lack available molecular sequences, are transferred to Umbellus as U. corneri, U. hamatus, and U. umbraculus. Hereafter, all known species with large umbrella-shaped crystalline-headed cystidia are in a single genus. In summary, the current study provides a supplement to the latest taxonomic framework of Hymenochaetales and will help to further explore species diversity and the evolution of this fungal order.

Nemania hydei sp. nov. (Xylariaceae) from Avicennia marina in Central Thailand

ABSTRACT A novel fungus species, Nemania hydei, isolated from Avicennia marina in Pranburi District, Prachuap Khiri Khan, Thailand is described. The samples were collected from mangrove habitats, and the fungus was isolated and characterised. Nemania species produce carbonaceous, superficial stromata that are multi-peritheciate with papillate ostioles. They are frequently isolated from decomposing angiospermous wood and are primarily considered saprophytic, although some are endophytic, while a few are pathogenic. DNA extraction was performed on pure cultures, and the ITS, LSU, RPB-2, and TUB sequence data were amplified. Molecular phylogenetic investigation revealed that the isolate formed a distinct and well-supported clade with Nemania viridis as a sister taxon. Morphological observations further demonstrated unique characteristics that distinguish N. hydei from its closest taxonomic relative. Primarily, they differ in the shape and size of ascospores, asci, and the characteristic reaction of the apical ring. Despite the existence of over 70 known species within the genus Nemania, only four species have been previously documented from mangrove ecosystems. The discovery of N. hydei contributes to knowledge of species from mangroves, expanding our understanding of the diversity within Nemania in marine habitats.

Seasonal dynamics of cell-to-cell transport in angiosperm wood.

This study describes the seasonal changes in cell-to-cell transport in three selected angiosperm tree species, Acer pseudoplatanus (maple), Fraxinus excelsior (ash), and Populus tremula × tremuloides (poplar), with an emphasis on the living wood component, xylem parenchyma cells (XPCs). We performed anatomical studies, dye loading through the vascular system, measurements of non-structural carbohydrate content, immunocytochemistry, inhibitory assays and quantitative real-time PCR to analyse the transport mechanisms and seasonal variations in wood. The abundance of membrane dye in wood varied seasonally along with seasonally changing tree phenology, cambial activity, and non-structural carbohydrate content. Moreover, dyes internalized in vessel-associated cells and 'trapped' in the endomembrane system are transported farther between other XPCs via plasmodesmata. Finally, various transport mechanisms based on clathrin-mediated and clathrin-independent endocytosis, and membrane transporters, operate in wood, and their involvement is species and/or season dependent. Our study highlights the importance of XPCs in seasonally changing cell-to-cell transport in both ring-porous (ash) and diffuse-porous (maple, poplar) tree species, and demonstrates the involvement of both endocytosis and plasmodesmata in intercellular communication in angiosperm wood.

Influences of Wood Decomposition Associated with Tree Types on Soil Nutrient Concentrations and Enzyme Activities

Wood decomposition is a biogeochemical process fundamental to element cycling in forest ecosystems, which could alter the nutrient concentrations and enzyme activities of the underlying forest soils. Wood traits, which vary by tree species, can influence decomposition aboveground, but it is not well understood how wood decomposition associated with different tree types (i.e., angiosperm and gymnosperm species) influences underlying soil nutrient concentrations and enzyme activities. In this study, we evaluated how tree type (for four angiosperm vs. four gymnosperm species) affects underlying soil total carbon (C), nitrogen (N), and phosphorus (P) concentrations; microbial biomass C, N, and P concentrations; and C-, N-, and P-acquiring enzymes activities. We found that decomposing wood significantly increased soil total P, and microbial biomass C and P concentrations. However, the differences in the nutrient concentrations of soil and microbial biomass beneath decomposing wood were not different between angiosperm and gymnosperm species. Surprisingly, the activities of soil C-, N-, and P-acquiring enzymes beneath the decomposing wood differed significantly between angiosperm and gymnosperm species. The soils beneath decomposing angiosperm wood had higher P-acquiring enzyme activity, while the soils beneath gymnosperm wood had higher C- and N-acquiring enzyme activities. The soils beneath angiosperm and gymnosperm wood had a similar C-limitation for microbial metabolism, but the microbial metabolism in soils beneath angiosperm wood was more P-limited compared to soils beneath gymnosperm wood. In conclusion, our findings highlight that the tree types of decomposing wood may affect underlying soil enzyme activities and enzyme characteristics, improving our ability to accurately predict the role of wood decomposition on forest nutrient cycles.

Pluteus flammans, a new brightly coloured species in Pluteus sect. Celluloderma (Pluteaceae) from Central Europe

In this article we describe a new species, Pluteus flammans, that is characterised by bright orange-red colours, a villose and translucently striate pileus, and a trichodermal pileipellis. The species is described based on material from Slovakia and Hungary, where it grows on well-decayed angiosperm wood (Quercus spp., Fagus sylvatica, and Tilia sp.). In the phylogenetic analyses (LSU, ITS and TEF1-α) P. flammans appears as sister to the North American Pluteus aurantipes, which also has brightly coloured basidiomes, however this species differs in the bright red stipe, darker colours of the pileus, slightly larger basidiospores, and shorter caulocystidia. Molecular data supports the recognition of both taxa as separate species, and confirms their placement in Pluteus sect. Celluloderma, despite the fact that P. aurantipes was originally considered to belong to Pluteus sect. Hispidoderma.

Toward a better understanding of angiosperm xylogenesis: a new method for a cellular approach.

The kinetics of wood formation in angiosperms are largely unknown because their complex xylem anatomy precludes using the radial position of vessels and fibers to infer their time of differentiation. We analyzed xylogenesis in ring-porous ash (Fraxinus angustifolia) and diffuse-porous beech (Fagus sylvatica) over 1 yr and proposed a novel procedure to assess the period of vessel and fiber enlargement using a referential radial file (RRF). Our approach captured the dynamics of wood formation and provided a robust estimation of the kinetics of vessel and fiber enlargement. In beech, fibers and vessels had a similar duration of enlargement, decreasing from 14 to 5 d between April and July. In ash, wide vessels formed in April enlarged at a rate of 27 × 103 μm2 d-1 , requiring half the time of contemporary fibers (6 vs 12 d), and less time than the narrower vessels (14 d) formed in May. These findings reveal distinct cell-type-dependent mechanisms for differentiation in diffuse-porous and ring-porous trees, enhancing our understanding of angiosperm wood cell kinetics. Our approach presents an effective method for investigating angiosperm wood formation and provides a more accurate representation of vessel and fiber morphogenesis in wood formation models.

A contribution to the genus Steccherinum (Steccherinaceae, Polyporales): Introducing two new species and two new combinations of the genus.

Two new wood-inhabiting fungi from China, Steccherinum juniperi and S. incrustans, in the family Steccherinaceae are described and illustrated based on morphological and molecular analyses. The species S. juniperi was found growing on the rotten wood of Juniperus in Qinghai Province, China, while S. incrustans was collected on rotten angiosperm wood in Yunnan Province, China. The characteristics of S. juniperi include annual, resupinate basidiomata with a buff yellow fresh pore surface that becomes apricot orange when bruised, angular pores of 3-6 per mm, subicular generative hyphae sometimes covered with crystals, the presence of encrusted skeletocystidia in tube trama only, fusiform to slim clavate cystidioles, and ellipsoid basidiospores measuring as 3-4 × 2-3 μm. The characteristics of S. incrustans include annual, resupinate basidiomata with a buff yellow or pinkish buff to clay buff dried pore surface, angular pores (8-10 per mm), generative hyphae in trama frequently covered with crystals, the presence of encrusted skeletocystidia in tube trama and hymenium, and ellipsoid basidiospores (3.5-4.5 × 2.5-3.5 μm). Phylogenetic analysis based on a combined 2-locus dataset [ITS1-5.8S-ITS2 (ITS) + nuclear large subunit RNA (nLSU)] shows that the two species are members of Steccherinum, and they are compared with morphologically similar and related species of this genus, respectively. In addition, two new combinations from Junghuhnia, transferred to Steccherinum as S. austrosinense and S. nandinae, are proposed based on examination of their type materials and phylogenetic analysis.

The role of imperforate tracheary elements and narrow vessels in wood capacitance of angiosperm trees

Summary There is a broad diversity of imperforate tracheary elements (ITEs) — libriform fibers, fiber-tracheids, true tracheids and vasicentric/vascular tracheids — described thoroughly by Sherwin Carlquist. However, in a quantitative sense, the functional meaning of different ITE types present in the wood of vessel-bearing angiosperms remains unclear because very few structure–function studies measure ITEs’ properties. ITEs with abundant pits and wide pit borders — vascular tracheids, vasicentric tracheids, and true tracheids sensu Carlquist — have been shown to conduct water and, thanks to this conductive ability and the multitude of pits, they could also contribute to wood capacitance. A dataset of 30 temperate angiosperm tree species was reanalysed to record the presence/absence of true, vasicentric, and vascular tracheids including data on conduits15 fraction and vessel-conduit15 contact fraction (conduits15 were defined as cells resembling vessels and with a maximum lumen diameter of 15 μm. They encompassed narrow vessels, vasicentric tracheids, and vessel tails). The presence of tracheids, conduits15 fraction, and contact fraction had no effect on wood capacitance, except, per given wood volumetric lumen water content, species with true tracheids tended to have lower capacitance. These results suggest that the presence of tracheids or conduits15 properties do not limit wood capacitance, but the results do not exclude the potential role these cells may play in internal water dynamics.

Fossil wood of Iceland: An overview and new finds in Miocene coal-bearing formations

As yet, palaeontological research of fossil wood of Iceland has identified several conifers of the families Pinaceae and?Podocarpaceae and one angiosperm of the family Fagaceae. Occurrence of other angiosperm woods of the families of Salicaceae, Betulaceae, Fagaceae and Aquifoliaceae was also mentioned in a palaeoclimatology study from Tjörnes but without any anatomical description. New research in xylitic wood of Miocene coal-bearing formations of the Botn, Gil, Dufansdalur and Brjánslækur localities documented the first occurrence of wood of the family Cupressaceae s.l., identified as Taxodioxylon aff. cryptomerioides, and also additional evidence of modern larch-similar wood of Piceoxylon arcticum (Pinaceae).

The evolution of mechanical properties of conifer and angiosperm woods.

The material properties of the cells and tissues of an organism dictate, to a very large degree, the ability of the organism to cope with mechanical stress induced by externally applied forces. It is, therefore, critical to understand how these properties differ across diverse species and how they have evolved. Herein, a large data base (N=84 species) for the mechanical properties of wood samples measured at biologically natural moisture contents (i.e., "green wood") was analyzed to determine the extent to which these properties are correlated across phylogenetically diverse tree species, to determine if a phylogenetic pattern of trait values exists, and, if so, to assess whether the rate of trait evolution varies across the phylogeny. The phylogenetic comparative analyses presented here confirm previous results that critical material properties are significantly correlated with one another and with wood density. Although the rates of trait evolution of angiosperms and gymnosperms (i.e., conifers) are similar, the material properties of both clades evolved in distinct selective regimes that are phenotypically manifested in lower values across all material properties in gymnosperms. This observation may be related to the structural differences between gymnosperm and angiosperm wood such as the presence of vessels in angiosperms. Explorations of rate heterogeneity indicate high rates of trait evolution in wood density in clades within both conifers and angiosperms (e.g., Pinus and Shorea). Future analyses are warranted using additional data given these preliminary results, especially because there is ample evidence of convergent evolution in the material properties of conifers and angiosperm wood that appear to experience similar ecological conditions.

Taxonomy and Phylogeny of Meruliaceae with Descriptions of Two New Species from China.

Two new wood-inhabiting fungi Hermanssonia fimbriata sp. nov. and Phlebia austroasiana sp. nov. in the Meruliaceae family are described and illustrated from southwestern China based on molecular and morphological evidence. The characteristics of H. fimbriata include annual, resupinate basidiomata, the absence of cystidia and cystidioles, oblong ellipsoid basidiospores of 5–6 × 2.4–3 μm, and growth on rotten gymnosperm wood in the east Himalayas. Its basidiomata change drastically upon drying, from being a light-coloured, juicy, papillose-to-wrinkled hymenophore, to a dark-coloured, corky-to-gelatinous, and more or less smooth hymenophore. The characteristics of Ph. austroasiana include annual, resupinate basidiomata, a hydnoid hymenophore, 2–3 spines per mm, the presence of tubular cystidia of 20–25 × 3–3.5 µm, oblong ellipsoid basidiospores of 4.4–5.2 × 2.1–3 μm, and growth on angiosperm wood in tropical forests in the southern Yunnan Province. The phylogenetic analyses based on the combined 2-locus dataset (ITS1-5.8S-ITS2 (ITS) + nuclear large subunit RNA (nLSU)) confirm the placement of two new species, respectively, in Hermanssonia and Phlebia s. lato. Phylogenetically, the closely-related species to these two new species are discussed.

A new species of Antella (Steccherinaceae, Agaricomycetes) from southwest China

A new poroid fungus in the family Steccherinaceae, Antella tibetica sp. nov., is described from southwest China based on morphology, and phylogenetic analysis. The species was found in the Tibet Autonomous Region of southwest China, growing on angiosperm wood of a low decay stage. It is characterized by an annual growth habit, resupinate basidiocarps with buff yellow to yellowish brown pores, 0.5–1.5 per mm, a dimitic hyphal system composed of clamped generative hyphae and subicular skeletal hyphae encrusted with fine crystals, abundant gloeocystidia that are variable in shape, and oblong-ellipsoid basidiospores. The phylogenetic analysis based on ITS + nLSU rDNA sequences shows that A. tibetica nests in Antella, forming a monophyletic lineage with strong support (100 % BS, 100 % BP, 1.00 BPP). The differences between A. tibetica and other members of the genus are discussed. A key to accepted species of Antella is provided.

A re-examination of the angiosperm wood record from the early and middle Miocene of Turkey, and new species descriptions

The early and middle Miocene in Turkey was characterised by a warm climate and a diversified and rich vegetation. Many fossil angiosperm genera have been identified from this period. The present study re-examined previously identified genera and identifed new samples of angiosperm wood remains. The studied material included thin sections housed at the Department of Forest Botany, Division of Forest Engineering, Faculty of Forestry, Istanbul University-Cerrahpasa, and also new ones. Twelve new species are described: Liquidambaroxylon efeae Akkemik sp. nov., Eucarpinoxylon kayacikii Akkemik sp. nov., Ostryoxylon gokceadaense Akkemik sp. nov., Quercoxylon yaltirikii Akkemik sp. nov., Cryptocaryoxylon grandoleaceum Akkemik sp. nov., Fraxinoxylon beypazariense Akkemik sp. nov., Prunoidoxylon prunoides Akkemik sp. nov., Populoxylon sebenense Akkemik sp. nov., Salicoxylon galatianum Akkemik sp. nov. Aceroxylon aceroides Akkemik sp. nov., Ulmoxylon kasapligilii Akkemik sp. nov. and Zelkovoxylon crystalliferum Akkemik sp. nov. In addition, four previously described species are documented for the early and middle Miocene: Pistacioxylon ufukii Akkemik and I. Poole, Fagoxylon radiatum Süss, Laurinoxylon litseoides Süss and Platanoxylon catenatum Süss and Müller-Stoll. In addition to the species descriptions, identification keys are given for all the genera recognised in this study, including all currently known fossil species of the respective fossil genera. These keys hold important new information, as they place the fossil species from Turkey in a wider taxonomic and biogeographic context. The results show that in the early and early-middle Miocene of Turkey a rich woody flora existed in well-drained upland or lowland and riparian areas. This flora comprised subtropical taxa along with warm-temperate taxa indicative of seasonality of rainfall as well as transitions to xeric conditions in the early Miocene.

<strong><em>Steccherinum fragile sp. nov.</em> and <em>S. subcollabens comb. nov.</em> (Steccherinaceae, Polyporales), evidenced by morphological characters and phylogenetic analysis</strong>

A new poroid wood-inhabiting fungus in the family Steccherinaceae, Steccherinum fragile sp. nov., is described and illustrated from China based on morphological and molecular evidence. The species was collected in Yunnan Province, growing on the ground and undersides of rotten angiosperm wood. S. fragile is characterized by an annual growth habit, resupinate basidiocarps with salmon to peach pores when fresh becoming cinnamon buff to pinkish buff upon drying, a thin margin with distinct rhizomorphs, a monomitic hyphal system, generative hyphae thin- to distinctly thick-walled with simple septa, neither amyloid nor cyanophilous. The phylogenetic analysis based on ITS + nLSU rDNA sequences shows that the new species belongs to Steccherinum, forming a monophyletic lineage with strong support (100% BS, 100% BP, 1.00 BPP). In addition, a new combination, S. subcollabens, is also proposed based on examination of its type material and phylogenetic analysis. Phylogenetically, Steccherinum fragile is closely related to S. amapaense and groups with S. subcollabens, S. formosanum and S. collabens. Both morphological and molecular characters confirm the placement of the new species and combination in Steccherinum.

Subfamily Anischiinae (Coleoptera: Eucnemidae) in Early Cretaceous of Northeast China.

Simple SummaryA new false click-beetle (Eucnemidae) belonging to subfamily Anischiinae, formerly not known as fossils, extends the age of this small extant group 125 million years back. The structural specializations of the false click-beetle larvae are discussed. On the basis of this new piece of paleontological evidence, it is shown that these insects have changed their host preference from gymnosperms to angiosperms at least twice. It also indicates that the beetle larvae can switch their favored development substrate by adapting in different ways, either with or without morphological specialization.Rheanischia new genus, type species Rheanischia brevicornis new species (Eucnemidae, Anischiinae) is described from the Lower Cretaceous of Liaoning, China. The presence of this species in early Cretaceous deposits provides new insight into the evolution of basal lignicolous Eucnemidae clades. Both Anischiinae and Palaeoxeninae species diversified in a world dominated by gymnosperms, before the main radiation of angiosperms. More than 95% of modern eucnemid larvae have a Palaeoxenus-type highly modified head structure, but contrary to the Palaeoxenus larva, they develop in angiosperm wood. Anischiinae utilize angiosperms as well, but their head capsule shows no such modifications. These facts prove that highly specialized morphological features do not offer definite proof of similar way of life in the distant past, nor should non-modified structures be taken as proof for another kind of substrate choice. Eucnemidae have invaded angiosperms with two quite different morphological adaptations. This fact may have implications for the evolution of all clicking elateroids.

Wood species automatic identification from wood core images with a residual convolutional neural network

This paper tackles the problem of automatic tree species identification from scanned images of wood cores. A convolutional neural network with residual connections is proposed to perform this task. The model is applied to consecutive image patches following the sliding window strategy to recognize a patch central pixel’s membership. It then decides about the resulting tree species via a majority voting. The model’s performance was assessed concerning a dataset of 312 wood core images representing 14 European tree species, including both conifer and angiosperm (ring-porous and diffuse-porous) wood. Two tasks were considered, including wood patch classification and wood core classification. In these tasks, the proposed model correctly recognized species of almost 93% the wood image patches and 98.7% of wood core images. It also outperformed the state-of-the-art convolutional neural network-based competitor by 9% and 3%, respectively. The influence of the model’s parameters and training set-up on its performance is analyzed in the manuscript to ensure the highest recognition rates of wood species. The source code of the proposed method is released together with the corresponding image dataset to facilitate the reproduction of results.

Charcoalified wood from the cenomanian of gard (Southern France): An insight into early angiosperm palaeoecology

The discovery in the Cenomanian (early Late Cretaceous) of Southern France of several localities with abundant charcoal has brought to light several angiosperm wood types. This is the oldest angiosperm wood assemblage discovered yet for Europe. Here we analyse this assemblage, with emphasis on features recognized to be of particular palaeoecological and climatic significance for the Cainozoic according to earlier studies and comparing the inferred results to those from other independent lines of evidence (sedimentology, palynology, isotopic geochemistry, etc.). Vessel diameter and distribution, perforation plates, abundance of vascular tracheids and of septate fibres, presence of diffuse axial parenchyma perhaps should not be used as palaeoecological proxies for the Cretaceous because they do not seem to clearly correlate with other lines of evidence that indicate warm tropical conditions. The abundance of fibre-tracheids fits with the other sources of data, but our results are probably biased by preservation problems. On the contrary, the occurrence of growth-rings, porosity, vessel density, occurrence of vessel groups, occurrence of vasicentric tracheids and of some paratracheal to vasicentric and banded axial parenchyma correlate well with other palaeoclimate indicators. These results show that these features can be used for palaeoclimatological inferences during the early Late Cretaceous