Kurzawe F.,Federal University of Rio Grande do Sul |
Iannuzzi R.,Federal University of Rio Grande do Sul |
Merlotti S.,Federal University of Santa Catarina |
Rossler R.,Museum fur Naturkunde Chemnitz |
Noll R.,In den Birkengarten 30
Review of Palaeobotany and Palynology | Year: 2013
The Permian permineralized flora of the Parnaíba Basin, NE Brazil, has been studied since 1872, when the first fossil fern was described from this region. Since then, many fossil pteridophytes have been collected and studied; however, the gymnosperms are still little known. The present contribution focuses on the study of gymnospermous woods from the Motuca Formation. This study presents four new taxa of which three are formally described: Ductoabietoxylon solis gen. et sp. nov., Scleroabietoxylon chordas gen. et sp. nov., Parnaiboxylon rohnae gen. et sp. nov. and Parnaiboxylon sp. 1. The first two genera share an outstanding feature: the presence of abietinoid pitting, a rare characteristic among fossil woods, and a derived stage in the evolution of xylem rays. The presence of several new genera and species in the lowermost Motuca Formation reveals the richness and importance of this area for paleobotanical studies. © 2013 Elsevier B.V.
Viney M.,Poudre School District |
Viney M.,Colorado State University |
Dietrich D.,TU Chemnitz |
Mustoe G.,Western Washington University |
And 5 more authors.
Geosciences (Switzerland) | Year: 2016
The 1895 discovery of a petrified tree near Clover Creek in south-central Idaho, USA, attracted worldwide attention and resulted in the naming of a new species of ancient oak, Quercinium pliocaenicum Schuster. For more than a century, the discovery has largely been forgotten, even though specimens reside in reputable museums. Reinvestigation of the locality in 2014/2015 resulted in newly-collected specimens and a wealth of new data. Optical microscopy confirms the cellular anatomy used for the original taxonomic study. X-ray diffraction, scanning electron microscopy, energy-dispersive electron spectroscopy, Raman spectroscopy and cathodoluminescence microscopy reveal details of the mineralization, showing the presence of opal-CT as the primary component, with chalcedony as a lesser constituent. This mineralogy suggests petrifaction occurred in at least two stages, beginning with opalization of cellular tissue, leaving open vessels that became filled with chalcedony during a later mineralization episode. Clover Creek oak represents relict flora growing in a wetter climate before the uplift of the Cascade Range created a rain shadow that caused profound desertification of the inland Pacific Northwest. © 2016 by the authors; licensee MDPI, Basel, Switzerland.
Luthardt L.,Museum fur Naturkunde Chemnitz |
Rossler R.,Museum fur Naturkunde Chemnitz |
Schneider J.W.,TU Bergakademie Freiberg |
Schneider J.W.,Kazan Federal University
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2016
As significant indicators of deep-time palaeoclimate, a number of new palaeontological, pedological and geochemical characteristics are provided for the Chemnitz Fossil Lagerstätte to depict more precisely its environmental conditions. For the first time, several lines of evidence indicate that this fossil forest, instantaneously preserved by volcanic deposits, once received an annual precipitation of around 800-1100 mm, but grew on a nearly unweathered palaeosol. Although the composition of this rich and diverse T0 assemblage suggests a hygrophilous, dense and multi-aged vegetation dominated by conservative lineages, the habitat was affected by environmental disturbances and pronounced seasonality. Repeated changes in local moisture availability are suggested by geochemical proxies, the co-occurrence to intergrowth of calcic and ferric glaebules in the palaeosol and developmental traits of perennial vegetational elements. Specific substrate adaptation is reflected by different root systems and cyclic growth interruptions recorded in the stems, branches and roots of long-lived woody plants. Many differentially adapted terrestrial animals complete the more comprehensive reconstruction of a late Sakmarian ecosystem and its climatic and preservational controls. Albeit spatially confined, this diverse in-situ record may contribute to understand wetland-dryland dynamics of sub-tropical Northern Hemisphere Pangaea. © 2015 Elsevier B.V.
Dunlop J.A.,Leibniz Institute For Evolutions Und Biodiversitatsforschung |
Robler R.,Museum fur Naturkunde Chemnitz
Fossil Record | Year: 2013
A new trigonotarbid (Arachnida: Trigonotarbida) is described as Permotarbus schuberti n. gen., n. sp. from the Early Permian Petrified Forest (Rotliegend) of Chemnitz in Saxony (Germany). At ca. 290 Ma it represents the youngest record of this extinct arachnid order discovered to date. Its familial affinities are uncertain, but may lie close to the Aphantomartidae. The distribution of the trigonotarbid genera through time is summarised, together with a list of their seventy-seven fossil-yielding localities. Together they offer a broad overview of the group's fossil record, which is heavily biased towards the Moscovian Stage (ca. 307-312 Ma) of the Late Carboniferous in Europe and North America. This is due in no small part to numerous localities associated with coal mining districts, and trigonotarbids are found less frequently after this stage. While it is tempting to associate this with biological events - such as a putative 'Carboniferous Rainforest Collapse' dating to ca. 305 Ma - it is difficult to differentiate the effects of genuine extinction patterns from artefacts caused by fewer appropriate localities in the economically less relevant latest Carboniferous and Early Permian strata. Nevertheless, trigonotarbids became extinct at some point after the Early Permian and loss of the Coal Measures forests remains one of the most likely possible causes. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.