134 research outputs found
The early evolution of land plants, from fossils to genomics: a commentary on Lang (1937) âOn the plant-remains from the Downtonian of England and Wales'
© 2015 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited. The file attached is the published version of the article
Fertile Prototaxites taiti: a basal ascomycete with inoperculate, polysporous asci lacking croziers
The affinities of Prototaxites have been debated ever since its fossils, some attaining tree-trunk proportions, were discovered in Canadian Lower Devonian rocks in 1859. Putative assignations include conifers, red and brown algae, liverworts and fungi (some lichenised). Detailed anatomical investigation led to the reconstruction of the type species, P. logani, as a giant sporophore (basidioma) of an agaricomycete (= holobasidiomycete), but evidence for its reproduction remained elusive. Tissues associated with P. taiti in the Rhynie chert plus charcoalified fragments from southern Britain are investigated here to describe the reproductive characters and hence affinities of Prototaxites. Thin sections and peels (Pragian Rhynie chert, Aberdeenshire) were examined using light and confocal microscopy; PĆĂdolĂ and Lochkovian charcoalified samples (Welsh Borderland) were liberated from the rock and examined with scanning electron microscopy. Prototaxites taiti possessed a superficial hymenium comprising an epihymenial layer, delicate septate paraphyses, inoperculate polysporic asci lacking croziers and a subhymenial layer composed predominantly of thin-walled hyphae and occasional larger hyphae. Prototaxites taiti combines features of extant Taphrinomycotina (Neolectomycetes lacking croziers) and Pezizomycotina (epihymenial layer secreted by paraphyses) but is not an ancestor of the latter. Brief consideration is given to its nutrition and potential position in the phylogeny of the Ascomycota
Ăber einige fossile Hölzer aus Java
Da die Originale der von Göppert aus dem TertiĂ€r von Java beschriebenen Arten Piperites Hasskarlianus und Junghuhnites javanicus nicht mehr vorhanden sind, die vorliegenden Beschreibungen fĂŒr eine Bestimmung aber nicht ausreichen, so sind sie aus der fossilen Flora Javas zu streichen. Das gilt auch von Miquelites elegans, dessen schlechte Erhaltung eine sichere Bestimmung unmöglich macht. Bredaea moroides dagegen ist ebenso wie Naucleoxylon spectabile CriĂ© sowie ein bisher unbeschriebenes Kieselholz von Java eine Dipterocarpacee. Die StĂŒcke werden beschrieben als Dipterocarpoxylon moroides, D. spectabile und D. Göpperti n. sp. Die Frage, ob es möglich ist, diese wie andere fossile Dipterocarpoxyla bestimmten rezenten Dipterocarpaceengattungen zuzuweisen, soll spĂ€ter erörtert werden.
Frankfurt a/M. Geologisch-PalÀontologisches Institut der UniversitÀt
PROTEOKALON A NEW GENUS OF PROGYMNOSPERMS FROM THE DEVONIAN OF NEW YORK STATE AND ITS BEARING ON PHYLOGENETIC TRENDS IN THE GROUP
RELLIMIA THOMSONII, A NEW NAME FOR MILLERIA (PROTOPTERIDIUM) THOMSONII LANG 1926 EMEND. LECLERCQ AND BONAMO 1971
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