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Abstract: A new euphyllophyte, Planatophyton hujiersitense gen. et sp. nov., is described on the basis of adpression fossils collected from a late Early or Middle Devonian locality from the Hujiersite Formation in the Hujiersite area, Hoboksar County, North Xinjiang, North-West China. The plant is possibly rhizomatous and comprises main axes with alternately inserted lateral branching systems. All axis orders bear large triangular enations all over their surface. Lateral branching systems are up to six times dichotomous. Dichotomies in lateral branching systems occur in the same plane, which results in bilaterally symmetrical, two-dimensionally branched organs, with limited overlapping between any segments. Distal segments in sterile lateral branching systems look slightly flattened and/or webbed. The ultimate segments of fertile lateral branching systems bear Psilophyton-like pairs of pendulous twisted sporangia. Anatomy and spores of the plant are unknown. The implications of the new plant for the early evolution of multiveined leaf are evaluated. [Copyright &y& Elsevier]

Abstract: Cooksonia caledonica Edwards 1970 is a small Early Devonian plant, which presents some usual plesiomorphic characters for polysporangiophytes: isotomously branched axes, terminal sporangia. The plant was placed in the genus Cooksonia Lang 1937 on the basis of the “wider than high sporangium” character. The type material has been examined and is re-described. New large specimens, recently found in the Jackson de Figueiredo flora from the Paraná Basin, Brazil, are also studied. The sporangium of C. caledonica is bivalved and possesses a complex subdistal structure for dehiscence. It is different from that of the type species, C. pertoni Lang 1937, which is trumpet-shaped. The morphology of its sporangium clearly excludes the species C. caledonica from the genus Cooksonia. The sporangia of C. caledonica are comparable to those of Sporathylacium salopense Edwards et al. 2001a, which show the same organization. According to the ICBN, conspecificity of the two taxa cannot be established as they do not refer to the same biological structures. A new genus, Aberlemnia, is therefore erected for the plants formerly named C. caledonica. [ABSTRACT FROM AUTHOR]

Abstract: The proto-ovule Runcaria heinzelinii Stockmans 1968 has been re-described and interpreted as a precursor of seed plants; its generico–specifica diagnosis has been emended [Gerrienne, P., Meyer-Berthaud, B., Fairon-Demaret, M., Streel, M., Steemans, P. 2004. Runcaria, a Middle Devonian seed plant precursor. Science 306, 856–858.]. Here we define the concept of “proto-ovule” and designate an epitype to support the uninformative and poorly preserved holotype [Stockmans, F., 1968. Végétaux mésodévoniens récoltés aux confins du Massif du Brabant (Belgique). Inst. Roy. Sci. Nat. Belg. Mém. 159, 1–49., Plate VII: 8a]. [Copyright &y& Elsevier]

The Middle to early Late Devonian aneurophytalean progymnosperms represent the basalmost group of lignophytes and may have included the seed plant ancestor. They are widely recorded in Laurussia. Before this work, the only occurrences of Aneurophytales in Gondwana were in Venezuela and Morocco. In this paper we describe one fertile and two vegetative specimens of Tetraxylopteris from the Bunga beds at Bunga Pinch Quarry, a locality near Tathra on the south coast of New South Wales. The vegetative specimens consist of two orders of axes, the last order bearing alternately arranged ultimate appendages. Ultimate appendages are three-dimensional, highly dissected, and composed of terete segments of unequal length. The shape and arrangement of the ultimate appendages suggest that the Australian specimens belong to a new species of Tetraxylopteris . The association of Tetraxylopteris with large lycopsids constrains the age of the Bunga beds to the Givetian–Frasnian interval. The range of dissected ultimate appendage morphologies displayed by the genus Tetraxylopteris may have been advantageous in habitats characterized by high light conditions. These morphologies do not show any specialization for lianescence. [ABSTRACT FROM AUTHOR]

Abstract: Charcoal results from an incomplete combustion of biological material in anoxic conditions and has a high potential for three-dimensional cellular preservation. Most of the Belgian Upper Devonian flora is known through compression fossils, mainly from the siliciclastic Evieux Formation; no charcoal-bearing layers had been reported to date. We have recently identified organic-rich beds from three late Famennian localities (Val-Dieu quarry, Trooz quarry and Arbre quarry). The three localities are described from the sedimentological point of view. The Arbre and Trooz quarries contain allochthonous specimens of charcoalified wood. They are identified as Callixylon in Arbre. In Trooz, the specimen belongs either to an undescribed species of Callixylon or to another taxon of woody (pro)gymnosperm. The Val-Dieu quarry, by contrast, yielded a more diverse charcoalified assemblage including leafy remains, branches and fertile axes related to ferns, sphenopsids and (pro)gymnosperms. This material experienced moderate transportation before burial. The Val-Dieu assemblage is exceptional for Late Devonian deposits as it represents a moderately disturbed litter interpreted as representing a swamp environment and its proximal margins. This assemblage is an illustration that the fossil charcoal record can provide a unique opportunity to study in fine detail the evolutionary history and past diversity of life. [Copyright &y& Elsevier]