Reflectance Transforming Imaging (RTI) produces photographs in which the angle of the light can be changed at will, allowing to investigate remotely minute details of the 3D structure of sub-planar ...objects. Here we apply this technique to the type specimen of Gingkophyllum grassetii, a vegetative shoot with putative ginkgophyte affinities from the early Permian of Lodève (France). Gingkophyllum grassetii, the type species of the genus, was originally described by Saporta in 1875 and has never been illustrated other than by drawings representing only portions of the shoot. Using RTI, we describe and illustrate the specimen and discuss some key features, such as the arrangement of the leaves on the shoot or the presence of abundant secretory structures. Through an historical account, we show how the lack of illustration led to confusion about the morphology of Ginkgophyllum and we discuss the importance of reinvestigating type specimens of Paleozoic ginkgophyte taxa in order to clarify their taxonomy and better understand their evolutionary history. The sharing of RTI files is one example of approaches that can be further developed to improve remote access to specimens.
•Ginkgophyllum grassetii, the type species of the genus, is a putative Permian ginkgophyte.•Lack of published photos led to confusions about Ginkgophyllum morphology and taxonomy.•We re-investigate the type specimen using Reflectance Transforming Imaging.•We provide new information on the morpho-anatomy of the specimen.•RTI files could be further used to improve remote access to collection specimens.
Twelve species of fossil wood were identified from silicified specimens collected in the late middle Eocene Pondaung Formation, Myanmar. These species display affinities with modern Fabaceae, ...Moraceae, Combretaceae, Sapindaceae, Malvaceae, Dipterocarpaceae and Theaceae. They include five new species of the fossil genera Ficoxylon (F. mogaungense sp. nov.), Sapindoxylon (S. burmense sp. nov.), Bombacoxylon (B. pondaungense sp. nov.), Shoreoxylon (S. panganense sp. nov.) and Schimoxylon (S. benderi sp. nov.). This material represents the oldest record of fossil dipterocarps so far reported outside the Indian subcontinent. It reflects different ecotones of a dry dipterocarp forest, with coastal, riparian, and inland elements. The Burmese fossil assemblage further contrasts with the common idea that lowland rainforests were widespread in Southeast Asia during the Eocene. It suggests that the climate in the proto-Bengal Bay was more seasonal than previously thought. This confirms that early Dipterocarpaceae were adapted to seasonally dry climates, despite the modern prevalence of warm humid tropical species.
•We identify twelve fossil wood species in the late middle Eocene deposits of Myanmar.•Floral assemblage includes fossil Shorea-like dipterocarps.•Floral assemblage reflects different ecotones of a dry dipterocarp forest.•Middle Eocene climate in the proto Bengal Bay was significantly seasonal.•Dipterocarps were early adapted to seasonal climates.
335-330 million-year-old cherts from the Massif Central, France, contain exceptionally well-preserved remains of an early forest ecosystem, including plants, fungi and other microorganisms. Here we ...reinvestigate the original material prepared by Renault and Roche from collections of the Muséum National d'Histoire Naturelle, Paris, and present a re-evaluation of Oochytrium lepidodendri (Renault 1894), originally described as a zoosporic fungus. Confocal laser scanning microscopy (CLSM) was used to study the microfossils, enabling us in software to digitally reconstruct them in three-dimensional detail. We reinterpret O. lepidodendri as a pseudofungus and favour placement within the oomycetes, a diverse clade of saprotrophs and both animal and plant parasites. Phylogenetically, O. lepidodendri appears to belong to a group of oomycetes distinct from those previously described from Paleozoic rocks and most likely related to the Peronosporales s.l. This study adds to our knowledge of Paleozoic eukaryotic diversity and reinforces the view that oomycetes were early and diverse constituents of terrestrial biotas, playing similar ecological roles to those they perform in modern ecosystems.
The Paleocene-Eocene Thermal Maximum (PETM) is correlated with the first occurrences of earliest modern mammals in the Northern Hemisphere. The latest Paleocene Clarkforkian North American Land ...Mammal Age, that has yielded rodents and carnivorans, is the only exception to this rule. However, until now no pre-PETM localities have yielded modern mammals in Europe or Asia. We report the first Clarkforkian equivalent Land Mammal Age in the latest Paleocene deposits of the basal Sparnacian facies at Rivecourt, in the north-central part of the Paris Basin. The new terrestrial vertebrate and macroflora assemblages are analyzed through a multidisciplinary study including sedimentologic, stratigraphic, isotopic, and palynological aspects in order to reconstruct the paleoenvironment and to evaluate biochronologic and paleogeographic implications. The mammals are moderately diverse and not abundant, contrary to turtles and champsosaurs. The macroflora is exceptional in preservation and diversity with numerous angiosperms represented by flowers, fruits, seeds and wood preserved as lignite material, revealing an abundance of Arecaceae, Betulaceae, Icacinaceae, Menispermaceae, Vitaceae and probably Cornaceae. Results indicate a Late Paleocene age based on carbon isotope data, palynology and vertebrate occurrences such as the choristoderan Champsosaurus, the arctocyonid Arctocyon, and the plesiadapid Plesiadapis tricuspidens. However, several mammal species compare better with the earliest Eocene. Among these, the particular louisinid Teilhardimys musculus, also recorded from the latest Paleocene of the Spanish Pyrenees, suggests a younger age than the typical MP6 reference level. Nevertheless, the most important aspect of the Rivecourt fauna is the presence of dental remains of a rodent and a "miacid" carnivoran, attesting to the presence of two modern mammalian orders in the latest Paleocene of Europe. Interestingly, these two groups are also the only modern groups recorded from the latest Paleocene of North America, making Rivecourt the first direct equivalent to the Clarkforkian Land Mammal Age outside of North America.
Icacinaceae Miers are a well-described family. However, the family lacks a comprehensive guide to endocarp morphology, which would be an important tool for interpreting the family’s extensive fossil ...record of endocarp remains. In this survey, we describe fruits and endocarps of 88 species of Icacinaceae s. str., four of Icacinaceae s. lat. (now Metteniusaceae) and one of Oncothecaceae. We investigated the value of the endocarp in species recognition. In addition, we generated an Xper3 database with an associated e-key to increase the availability of raw data and the understanding of the characters used. This study documents great diversity in epicarp hairs, mesocarp thickness, endocarp ornamentation, tubercle shape (if present), endocarp structure and thickness, and the locule lining. Some morphological features appear diagnostic for individual genera. In particular, the genus Iodes Blume, which is very common in the fossil record, is the only clade with the three following characters: papillae on the inner locule lining, ridged ornamentation on the endocarp surface, and a vascular bundle embedded within the endocarp wall. Finally, we discuss issues related to the preservation of fruit material in herbarium collections.
• Premise of the study: Through a comparative study of the anatomy of palm stems and the development of an interactive web-based tool, the present paper aims to provide a method of identifying palm ...stems. The stem determination will allow specialists in archaeology and paleontology to better exploit palm fossils for paleoenvironmental interpretations. The precise anatomical description also provides new systematic data tested in phylogenetic analyses (new anatomical characters, stratigraphic calibrations).• Methods: Stem samples were collected, including representatives from each tribe of the five palm subfamilies, and 25 descriptors (with 78 states) were defined within 37 taxa and registered in Xper2, a management tool for taxonomic description that allows editing of standardized descriptions. Some descriptors were used for the first time in this work; others were compiled from the existing literature. While all the palm subfamilies were included in the present study, the focus here is on the Coryphoideae.• Key results: Descriptors were mainly based on the general organization of the transverse section and the structure of the fibrovascular bundles as well as ground parenchyma. Coryphoideae have 1, 2, or more metaxylem elements, whereas the other subfamilies systematically present only 1 or 1 and 2 metaxylem elements. The centrifugal differentiation of the sheath of phloem fibers is described in other subfamilies but is not found in the Coryphoideae (except in Caryoteae).• Conclusion: Some tribes are easy to identify (Borasseae, Cryosophileae, Phoeniceae, Caryoteae); others are rather heterogeneous and more difficult to define (Chuniophoeniceae, Trachycarpeae). Caryoteae presents some unique states of the Arecoideae.
The Oligocene-early Miocene Chitarwata Formation records a critical interval of terrestrial sedimentation that predates the Siwalik deposits on the Potwar Plateau of north-central Pakistan. This ...Oligocene-early Miocene time interval has long been considered as lacking in the entire Indo-Pakistan region. The Chitarwata Formation is widely exposed in the Sulaiman Range, but has never been described in detail in the Sulaiman Lobe, where the famous fossiliferous strata called ‘Bugti Bone Beds’ have been known for over a century and half. The Chitarwata Formation represents coastal-delta at the base, and plain and fluvial environments at the top. Lithofacies and sedimentary structures of the Chitarwata Formation in the Bugti area are described in detail, and show a clearly distinct lithologic pattern, different from that reported from the Zinda Pir area. The Chitarwata Formation also records an important transition in the evolution of the drainage systems in the area during the late Paleogene and early Neogene. This transition from the west-flowing paleo-Indus fluvial system to the development of the ancestral Indus drainage system may explain the numerous hiatuses that characterize the Chitarwata Formation. The abundance of fossil mammals from the Chitarwata and overlying Vihowa formation in the Bugti Hills provides critical biochronologic information that sheds new light on biostratigraphic correlation with the Zinda Pir area and for the entire Sulaiman Range.
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