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Article Reference Flabellopteris lococannensis gen. et sp. nov.: A new fern-like plant from the Famennian of South Africa
A new fossil plant, Flabellopteris lococannensis Gess and Prestianni gen. et sp. nov., is described from the Famennian of South Africa. This plant is interpreted as monopodial in habit with a first order axis that only occasionally dichotomizes. The lateral organs (both branches and appendages) are borne spirally on all branching orders and a 1/3 organotaxy is suggested. The first order axes bear both second order axes and fertile appendages at the same nodes. Axes of the second and third branching orders bear appendages made of several isotomous dichotomies. Recurved paired sporangia are borne on dichotomizing appendages that are like the vegetative appendages. The plant bears some similarity to the Iridopteridales but also to the Late Devonian Rhacophytales and to the Lower Carboniferous fernlike plant Chlidanophyton dublinensis. The architecture of the plant is briefly discussed and its implication on the evolution of the frond is considered.
Located in Library / RBINS Staff Publications 2022
Article Reference ECMAScript program Morphological disparity of extant and extinct pinaceous ovulate cones: How many cones are enough?
Premise The expansion of Pinaceae during the Cretaceous is exemplified by the numerous ovulate cone taxa found in western Europe and North America. The Belgian Wealden facies deposits have delivered hundreds of exceptionally well-preserved yet isolated pinaceous ovulate cones; these cones were placed by convention within form-genera. Ten species have been described in Belgium, representing about 20% of the known fossil record of this period. However, the validity of these taxa is questionable because their intra- and interspecific variabilities have never been thoroughly studied. Moreover, quantifying the expansion of Pinaceae in terms of morphospace occupation is desirable to reveal the dynamics of this critical radiation. Methods We used linear and geometric morphometry to quantify the shape of the extensive sample of Cretaceous cones of Belgium. These methods were also applied to extant pinaceous species to compare the morphological disparity of Cretaceous assemblages against those of today in selected ecosystems. We used ordination methods (PCA) to visualize morphospace occupation and test for species delineation. Results The morphological disparity was not higher in fossil species than in extant species we sampled. Both morphological approaches confirmed that the species Pityostrobus andraei presents high morphological variability. Our resampling tests indicate that ovulate cone morphological variability can be satisfactorily quantified with as few as 15 specimens. Conclusions The methodology used here is relevant for quantifying both the variability and the diversity of many fossil assemblages, paving the way for a more robust evaluation of Cretaceous pinaceous diversity.
Located in Library / RBINS Staff Publications 2022
Article Reference Porongodendron minitensis gen. nov. sp. nov. a new lycopsid from the Mississippian of Argentina with adaptations to tundra-like conditions
The Mississippian is characterized worldwide by a general cooling of the environment and a climatic stratification of Earth. Argentina at that time was part of the megacontinent Gondwana. It occupied a position close to the South Pole around 60°S. Whereas paleoequatorial and paleotropical floras are relatively well known, higher latitude environments are still poorly understood. In this framework, a revision of Mississippian deposits is ongoing in Argentina. An extensive and detailed survey of the Sierra de las Minitas (La Rioja Province, western Argentina) involved drawing detailed sections and the systematic verification of all rock layers. Fossils were sampled and studied in the laboratory. We describe a new isoetalean lycopsid with a rare combination of characters. This plant presents an estimated low stature (approximately 30 cm), a branched rhizomorph, an inflated intermediary zone, a monocaulous growth form and evidence for cyclic fertility. These features are interpreted as representing specific adaptations to the harsher tundra conditions prevailing in the Lower Carboniferous Southern Polar environments.
Located in Library / RBINS Staff Publications 2022
Article Reference Revisiting the Rebreuve plant assemblage from the Lower Devonian of Artois, northern France
French Lower Devonian floras are rare, especially compared to certain other Western European countries. In this study, we reassess an assemblage collected in the 1930s in the Rebreuve quarry (Pas-de-Calais, northern France). We describe new features in several taxa and update taxonomic names from original descriptions. For instance, re-examination of vegetative remains previously described as Psilophyton princeps, led to the discovery of fertile structures allowing us to refer these specimens to Sawdonia. In total, this flora consists of 10 taxa, including up to four different Psilophyton species, such as P. parvulum. Other taxa include Danziella artesiana, Drepanophycus cf. spinaeformis, Sporogonites exuberans and some speci-mens of Taeniocrada and Sciadophyton, revealing a diverse Lower Devonian plant assemblage. The Rebreuve assemblage represents a typical Emsian flora from Laurussia and bears striking resemblance with coeval Belgian assemblages. Previous palynological investigations, in addi-tion to the similarities with well-dated Belgian floras, suggest an early Emsian age for this assemblage. The paleogeographical implications of findings are discussed.
Located in Library / RBINS Staff Publications 2022
Article Reference Plant-insect interactions in the Selandian (Early Paleocene) Gelinden Fossil Flora (Belgium) and what they mean for the ecosystems after the Cretaceous-Paleogene mass extinction
This study aims to quantify the intensity and diversity of plant-insect associations observed in the fossil assemblage of Gelinden, Limburg, Belgium. The site yields a rich collection of well-preserved plant remains, mainly leaves, from a Paleocene European temperate forest. The 780 specimens presented here were scanned using standardized morphotype systems for any trace of damage. This raw data was then used to quantify the intensity and diversity of interactions in the Gelinden flora. This material showed an impressive richness of interactions, contrasting with the poor North American sites covering the period that followed the Cretaceous-Paleogene extinction. Both hosts and interaction types observed at Gelinden are two to three times more abundant than in most American floras, in raw numbers and leaf area affected. This is coherent with what has been observed in the few other studies conducted in Europe, South America and Antarctica, pointing toward more regionalized effects of the extinction than previously assumed based on American findings. This greater richness implies that these sites were either less affected or quicker to recover from the Cretaceous/Paleogene extinction, questioning its global impact, at least on the lower levels of the food web, as discussed in the following paper.
Located in Library / RBINS Staff Publications 2023
Article Reference Fluvial activity of the Lateglacial to Holocene "Bergstraßenneckar" in the Upper Rhine Graben near Heidelberg, Germany – first results.
Located in Library / RBINS Staff Publications 2022
Article Reference An archaeocete vertebra re-examined: indications for a small-sized species of Pachycetus from Spain, Europe
Located in Library / RBINS Staff Publications 2023
Article Reference Iguanian lizards (Acrodonta and Pleurodonta) from the earliest Eocene (MP7) of Dormaal, Belgium: The first stages of these iconic reptiles in Europe
We here report on iguanians (both new and the previous record) from the earliest Eocene (MP 7) of the Dormaal locality in Belgium, from the time of the warmest global climates of the past 66 million years. Today iguanians are distributed mainly in the New World (Pleurodonta) and Old World (Acrodonta), having complicated biogeographic histories. Both lineages co-existed in Dormaal 56 Ma. Iguanians here document the presence of thermophilic faunas during greenhouse conditions in the northern mid-latitudes (above 50° north, the latitude of southern England). The complete maxilla of the agamid Tinosaurus europeocaenus is described and figured for the first time, being distinctive and furnishing a number of diagnostic characters. The dentary coronoid process of this species is also observed for the first time. Our morphological analysis supports the previous observation that Tinosaurus is similar to Leiolepis, but also differs from it by several distinguishing features. Some jaw character states present in T. europeocaenus are shared with the Indian T. indicus, Chinese T. doumuensis, and American Tinosaurus sp., but several differences among them are observed. Besides the wellknown Geiseltaliellus, we here erect and describe a new pleurodontan taxon. The new taxon is represented by a maxilla with a unique and peculiar tooth crown morphology: the central cusp is bifurcated, markedly split into two distinct and wellseparated “prongs.” This morphology likely indicates a high specialization on feeding sources. This might cause a higher extinction risk relative to generalists, because terrestrial ecosystems in Europe changed substantially during the Paleogene.
Located in Library / RBINS Staff Publications 2023
Article Reference New postcranial elements of mesonychid mammals from the Ypresian of France: New hypotheses for the radiation and evolution of the mesonychids in Europe
New postcranial elements of two mesonychids that lived during the Ypresian (early Eocene) in Europe are here described. The postcranial bones found at La Borie (France; ≈MP8 + 9) can be confidently ascribed to Hyaenodictis raslanloubatieri, while the astragalus found at Palette (France; ≈MP7) probably represents H. rougierae. Our study demonstrates that H. raslanloubatieri and H. rougierae were digitigrade in posture and relatively cursorial in locomotion. A single lumbar vertebra was recovered at La Borie and referred to H. raslanloubatieri; this element suggests this species was a moderately dorsostable predator. In addition, we illustrate the first maxillary fragment referable to H. raslanloubatieri, also discovered at La Borie. In comparison, we describe the postcranial elements of Pachyaena gigantea partially published in the early twentieth century, probably a plantigrade predator species. Morphological data derived from the La Borie specimens were included in phylogenetic analyses and support the reinstatement and monophyly of Hyaenodictis. Hyaenodictis was considered to be a junior synonym of Dissacus, but here we find that the Hyaenodictis clade includes almost all European mesonychids formerly referred to Dissacus along with the North American Wasatchian species H. willwoodensis.
Located in Library / RBINS Staff Publications 2023 OA
Inbook Reference L’environnement végétal et climatique
Located in Library / RBINS Staff Publications