Review of Palaeobotany and Palynology, Mar 1, 1996
Peltaspermum retensorium (Zalessky) Naugolnykh et Kerp, comb. nov., a new representative of the P... more Peltaspermum retensorium (Zalessky) Naugolnykh et Kerp, comb. nov., a new representative of the Peltaspermales, is described from the Kungurian of the Fore-Urals. Peltaspermum retensorium has radially symmetrical ovuliferous discs. The pollen organs are similar to those of other peltasperms. With regard to the frond architecture and the cuticle, the foliage of this plant appears to be very similar to that of Autunia Krasser emend. Kerp, a genus of peltasperms with bilaterally symmetrical megasporophylls, known from the uppermost Carboniferous and Lower Permian. Peltaspermum retensorium is the oldest true peltasperm with radially symmetrical ovuliferous organs known from Angaraland.
International Journal of Plant Sciences, Sep 1, 2019
Premise of research. Typical plant groups of the late Paleozoic Cathaysian floras from East and S... more Premise of research. Typical plant groups of the late Paleozoic Cathaysian floras from East and Southeast Asia include noeggerathialeans, gigantopterids, and endemic pteridosperms, but also cordaitaleans are abundant peat-forming elements. Even though coal ball floras have allowed whole-plant reconstructions of some cordaites, the classification of Cathaysian cordaitalean foliage still largely relies on macromorphological features. The Lower Shihhotse Formation (Guadalupian; Permian) exposed in the Palougou section in Shanxi, North China, hosts well-preserved macrofloras with abundant, large Cordaites leaves accompanied by typical Cathaysian genera, such as Tingia, Yuania, Cathaysiopteris, and Emplectopteris. Pivotal results. Bulk macerations have yielded abundant, exceptionally well-preserved cordaite cuticles, including the first records of axes, cones, seeds, and complete dwarf-sized leaves. Similarities in diagnostic epidermal features—especially in the characteristic stomatal architecture and arrangement—as well as the presence of in situ pollen grains recovered from cones and seeds allow us to reconstruct these organs into a single whole-plant cordaitalean species. Conclusions. The unique combination of characters enables the erection of a new genus and species, Wangjunia microphylla. The unusual quality of preservation of the various cuticle remains allows detailed comparisons of this new species with other Cathaysian and Euramerican Cordaitales. Wangjunia microphylla may be a representative of a distinctive cordaitalean lineage that inhabited the North China microcontinent from the Late Carboniferous to the middle Permian.
Abstract More than 100 specimens of a delicate microorganism are attached to a charophyte branch ... more Abstract More than 100 specimens of a delicate microorganism are attached to a charophyte branch that is located within a microbial mat dominated by the filamentous cyanobacterium Croftalania venusta from the Lower Devonian Windyfield chert (Scotland). Specimens are up to 30 μm and comprised of a narrow stalk to which an inverted lacrimoid or funnel-shaped cell is attached. The fossils are reminiscent of certain present-day heterokonts, lower fungi, and ciliophores, but the systematic affinities remain elusive. We hypothesize that the microbial mat framework had a cushioning effect on destructive mechanical forces such as water movement and, hence, was effective as a conservation trap for the delicate microorganisms.
Unusual microfossils that occurred associated with fungal spores in the Lower Devonian (~410 mya)... more Unusual microfossils that occurred associated with fungal spores in the Lower Devonian (~410 mya) Windyfield chert from Scotland were composed of a narrow stipe (2.5-9 lm long) to which was attached an obovoid or elongate dropshaped cell up to 14 lm long; a basal attachment pad was present in several specimens. The fossils were strikingly similar morphologically to certain present-day unicellular freshwater Tribophyceae and Chlorophyceae, but affinities to the fungal phylum Chytridiomycota also cannot be ruled out. This discovery adds to the inventory of distinctive microbial morphologies in the early non-marine paleoecosystems.
• Background and Aims Structurally preserved arbuscular mycorrhizas from the Lower Devonian Rhyni... more • Background and Aims Structurally preserved arbuscular mycorrhizas from the Lower Devonian Rhynie chert represent core fossil evidence of the evolutionary history of mycorrhizal systems. Moreover, Rhynie chert fossils of glomeromycotan propagules suggest that this lineage of arbuscular fungi was morphologically diverse by the Early Devonian; however, only a small fraction of this diversity has been formally described and critically evaluated. • Methods Thin sections, previously prepared by grinding wafers of chert from the Rhynie beds, were studied by transmitted light microscopy. Fossils corresponding to the description of Archaeospora spp. occurred in 29 slides, and were measured, photographed and compared with modern-day species in that genus. • Key Results Sessile propagules <85 µm in diameter, some still attached to a sporiferous saccule, were found in early land plant axes and the chert matrix; they developed, in a similar manner to extant Archaeospora, laterally or centrally within the saccule neck. Microscopic examination and comparison with extant fungi showed that, morphologically, the fossils share the characters used to circumscribe the genus Archaeospora (Glomeromycota; Archaeosporales; Archaeosporaceae). • Conclusions The fossils can be assigned with confidence to the extant family Archaeosporaceae, but because molecular analysis is necessary to place organisms in these taxa to present-day genera and species, they are placed in a newly proposed fossil taxon, Archaeosporites rhyniensis.
Photoautotrophic microorganisms were likely abundant in the Early Devonian Rhynie ecosystem;howev... more Photoautotrophic microorganisms were likely abundant in the Early Devonian Rhynie ecosystem;however, documented evidence of these life forms is rare. Hagenococcus aggregatus nov. gen. et sp. occurs in the Rhynie chert matrix as solitary cells, dyads, triads, linear, decussate, and isobilateral tetrads, sarcinoid packets, short filaments, irregular aggregations, and colonies. Individual cells are 15-40(->55) mu m in diameter. While it cannot be ruled out that H. aggregatus is a large cyanobacterium, affinities to the Chlorophyta or Streptophyta are far more likely. Some of the cells contain a prominent, spheroid inclusion which might represent the pyrenoid. Hagenococcus aggregatus expands our knowledge of the diversity of primary producers in Paleozoic non-marine ecosystems.
The impact of the variations in the chemical composition of higher vascular plant cuticles on the... more The impact of the variations in the chemical composition of higher vascular plant cuticles on their fossil record is usually not considered in paleobotanical and, more particularly, taphonomic studies. Here we address the subject with reference to the chemical characterization of insoluble cuticular matrices of a large variety of recent and fossil cuticles. The cuticles were analyzed using Curie-point pyrolysis-gas chromatographic techniques. Cuticular matrices of extant higher plants consist either of the biopolyester cutin, the insoluble, non-hydrolyzable polymethylenic biopolymer cutan, or a mixture of both biopolymers. In fossil cuticles an additional cuticular matrix type consisting of cutan and cutin-derived material is recognized. On the basis of the variations in their chemical composition and the different behavior of the cuticular constituents (viz., cutin and cutan) during diagenesis, it is concluded that the paleobotanical record of cuticles will be biased toward taxa originally having a significant amount of cutan in their cuticular matrix.
Starch is a major component in the human diet, and the acquisition of starch-rich food sources is... more Starch is a major component in the human diet, and the acquisition of starch-rich food sources is considered a pivotal step in the biological and cultural evolution of humankind. However, the potential role of starch as an energy vector in paleo-ecosystems has never been addressed, obviously due to the lack of tangible records of preQuaternary starch grains. Here we describe similar to 280-m. y.-old lycopsid megaspores from Permian forest-swamp deposits in north China that bear caps of granular material. Size, shape, and surface structures as well as chemical and optical properties of these grains show that these caps are masses of compound storage starch. This is by far the oldest unequivocal record of fossil starch known to date. Deposition outside the actual megaspore container makes it unlikely that these starches were used for embryo nutrition; moreover, ultrathin sections of the megaspores indicate that they may have been produced after the megaspores were fertilized. By analogy to the elaiosomes on seeds of zoochorous plants today, we suggest that these starch caps were used to attract and reward animals, possibly land arthropods or snails, for megaspore dispersal. This study offers a rare glimpse into early stages of plant-animal co-evolution in Permian swamp-forest ecosystems.
Comptes rendus de l'Académie des sciences. Série 2. Sciences de la terre et des planètes, Apr 1, 1998
Three different types of climbing organs of seed ferns are reported from the Upper Stephanian (Cp... more Three different types of climbing organs of seed ferns are reported from the Upper Stephanian (Cppermost Carboniferous) of central France on the basis of cuticular material. These three types are climber hooks, tendrils and branched tendrils terminating in adhesive discs. All are very similar to climbing organs of modern angiosperms. These discoveries demonstrate the potential of cuticulal analysis for the reconstruction of growth habits of fossil plants. Moreover, they exemplify that climbing and scrambling were common life strategies among Late Carboniferous seed ferns. The increasing proportion of climbing seed ferns in the Stephanian is interpreted as an expression of changing community structures of Late Palaeozoic coal swamp forests. C Academic de sciences / Elsevier, Paris.
Palaeogeography, Palaeoclimatology, Palaeoecology, Oct 1, 2019
Palynological assemblages from the Tulong succession in South Tibet enabled the recognition of th... more Palynological assemblages from the Tulong succession in South Tibet enabled the recognition of three miospore biozones within the Zhangdong and 'Yali' formations. In ascending order, they are the Retispora lepidophyta-Verrucosisporites nitidus (LN) Biozone, the Vallatisporites vallatus-Foveosporites pellucidus (VP) Biozone and the Rugospora polyptycha-Tricidarisporites arcuatus (PA) Biozone. The LN Biozone in the Tulong section can be correlated to the LN Biozone of Western Europe, based on
This paper provides the first description of the cuticles ofLescuropteris genuina, a pteridosperm... more This paper provides the first description of the cuticles ofLescuropteris genuina, a pteridosperm from the Upper Stephanian of the Blanzy-Montceau Basin, Central France. The status of the genusLescuropteris, which is often compared withOdontopteris, is discussed. However, cuticles seem to justify a separate status. Of special interest is the discovery of a modified pinna terminal with well developed tendrils, providing evidence
Fungi today enter into relationships with other fungi in many ways. Although this was likely also... more Fungi today enter into relationships with other fungi in many ways. Although this was likely also the case in the geologic past, detailed descriptions of interfungal associations and interactions based on fossils remain scarce. Sporocarps bounded by a peridium-like envelope occur singly within the lumen of large glomeromycotan spores (Palaeomyces gordonii var. major) from the Lower Devonian Rhynie chert. The envelope consists of multi-branched, interlacing hyphae. At the tips of hyphae, extending from the envelope into the lumen are produced spheroidal to urn-shaped spores. Similar sporocarps are found in several present day species in the Glomeraceae. Clusters of spores, superficially resembling sporocarps, may also
The growth habit of the Late Carboniferous-Early Permian pteridosperm Pseudomariopteris busquetii... more The growth habit of the Late Carboniferous-Early Permian pteridosperm Pseudomariopteris busquetii is reconstructed based on compression material from the upper Stephanian of the Blanzy-Montceau and Commentry Basins (Massif Central, France), and the upper Rotliegend of the Saar-Nahe Basin (Nahe Group, N 4, Rheinland Pfalz, Germany). Pseudomariopteris busquetii was a medium-sized, vine- to liana-like plant with slender stems to which small bipartite fronds were attached. What is most interesting is that the species used at least two different strategies to both anchor and support the plant body. Most specimens possess specialized climber hooks developed from apical extensions of the pinna axes, indicating that the fronds were used to attach the plant. A few specimens suggest that the stem may also have had some capacity for attachment. In the absence of suitable supports, however, P. busquetii was apparently able to grow in dense stands or thickets in which the individual plants supported each other.
Review of Palaeobotany and Palynology, Mar 1, 2007
The Carnian flora from Lunz (Lower Austria) ranks among the richest and most diverse fossil flora... more The Carnian flora from Lunz (Lower Austria) ranks among the richest and most diverse fossil floras from the Upper Triassic. It is one of the first modern Triassic floras with bennettitaleans. Although this flora is often referred to in the literature, modern taxonomic studies are mostly absent; only some of the reproductive structures have been studied in detail. Many of the plant remains yield excellently preserved cuticles. During a systematic study of the Pterophyllum leaves from Lunz, it appeared that several species previously ...
Review of Palaeobotany and Palynology, Feb 1, 2010
The Bennettitales are a Mesozoic group of gymnosperms with complex reproductive organs that figur... more The Bennettitales are a Mesozoic group of gymnosperms with complex reproductive organs that figure prominently in hypotheses on the ancestry and origin of angiosperms. However, the exact phylogenetic position of the Bennettitales is still debated, due in part to the scarcity of conclusive fertile remains from the Triassic. In this study we reconstruct a bennettitalean flower from isolated parts from the Carnian (Upper Triassic) of Lunz in Lower Austria, including Cycadolepis wettsteinii scale leaves, Haitingeria krasseri pollen organs, and Bennetticarpus wettsteinii ovulate organs/seed cones, based on correspondences in gross morphology and epidermal anatomy. The flower has small pollen organs with spreading and well-exposed pollen sacs; pollen sacs are not organised in synangia, and the ovulate organ is characterised by a low number of relatively large seeds and a large number of interseminal scales in relation to ovules/seeds. The flower lacks several of the characteristic features seen in geologically younger bennettitaleans, including fused, inwardly curved pollen organs and large number of small seeds. The association of these isolated organs to a single flower provides a rare opportunity to assess the attribution of these early representative of the Bennettitales, and sheds new light on the evolutionary history and phylogenetic position of this ancient group of seed plants.
Review of Palaeobotany and Palynology, Mar 1, 1996
Peltaspermum retensorium (Zalessky) Naugolnykh et Kerp, comb. nov., a new representative of the P... more Peltaspermum retensorium (Zalessky) Naugolnykh et Kerp, comb. nov., a new representative of the Peltaspermales, is described from the Kungurian of the Fore-Urals. Peltaspermum retensorium has radially symmetrical ovuliferous discs. The pollen organs are similar to those of other peltasperms. With regard to the frond architecture and the cuticle, the foliage of this plant appears to be very similar to that of Autunia Krasser emend. Kerp, a genus of peltasperms with bilaterally symmetrical megasporophylls, known from the uppermost Carboniferous and Lower Permian. Peltaspermum retensorium is the oldest true peltasperm with radially symmetrical ovuliferous organs known from Angaraland.
International Journal of Plant Sciences, Sep 1, 2019
Premise of research. Typical plant groups of the late Paleozoic Cathaysian floras from East and S... more Premise of research. Typical plant groups of the late Paleozoic Cathaysian floras from East and Southeast Asia include noeggerathialeans, gigantopterids, and endemic pteridosperms, but also cordaitaleans are abundant peat-forming elements. Even though coal ball floras have allowed whole-plant reconstructions of some cordaites, the classification of Cathaysian cordaitalean foliage still largely relies on macromorphological features. The Lower Shihhotse Formation (Guadalupian; Permian) exposed in the Palougou section in Shanxi, North China, hosts well-preserved macrofloras with abundant, large Cordaites leaves accompanied by typical Cathaysian genera, such as Tingia, Yuania, Cathaysiopteris, and Emplectopteris. Pivotal results. Bulk macerations have yielded abundant, exceptionally well-preserved cordaite cuticles, including the first records of axes, cones, seeds, and complete dwarf-sized leaves. Similarities in diagnostic epidermal features—especially in the characteristic stomatal architecture and arrangement—as well as the presence of in situ pollen grains recovered from cones and seeds allow us to reconstruct these organs into a single whole-plant cordaitalean species. Conclusions. The unique combination of characters enables the erection of a new genus and species, Wangjunia microphylla. The unusual quality of preservation of the various cuticle remains allows detailed comparisons of this new species with other Cathaysian and Euramerican Cordaitales. Wangjunia microphylla may be a representative of a distinctive cordaitalean lineage that inhabited the North China microcontinent from the Late Carboniferous to the middle Permian.
Abstract More than 100 specimens of a delicate microorganism are attached to a charophyte branch ... more Abstract More than 100 specimens of a delicate microorganism are attached to a charophyte branch that is located within a microbial mat dominated by the filamentous cyanobacterium Croftalania venusta from the Lower Devonian Windyfield chert (Scotland). Specimens are up to 30 μm and comprised of a narrow stalk to which an inverted lacrimoid or funnel-shaped cell is attached. The fossils are reminiscent of certain present-day heterokonts, lower fungi, and ciliophores, but the systematic affinities remain elusive. We hypothesize that the microbial mat framework had a cushioning effect on destructive mechanical forces such as water movement and, hence, was effective as a conservation trap for the delicate microorganisms.
Unusual microfossils that occurred associated with fungal spores in the Lower Devonian (~410 mya)... more Unusual microfossils that occurred associated with fungal spores in the Lower Devonian (~410 mya) Windyfield chert from Scotland were composed of a narrow stipe (2.5-9 lm long) to which was attached an obovoid or elongate dropshaped cell up to 14 lm long; a basal attachment pad was present in several specimens. The fossils were strikingly similar morphologically to certain present-day unicellular freshwater Tribophyceae and Chlorophyceae, but affinities to the fungal phylum Chytridiomycota also cannot be ruled out. This discovery adds to the inventory of distinctive microbial morphologies in the early non-marine paleoecosystems.
• Background and Aims Structurally preserved arbuscular mycorrhizas from the Lower Devonian Rhyni... more • Background and Aims Structurally preserved arbuscular mycorrhizas from the Lower Devonian Rhynie chert represent core fossil evidence of the evolutionary history of mycorrhizal systems. Moreover, Rhynie chert fossils of glomeromycotan propagules suggest that this lineage of arbuscular fungi was morphologically diverse by the Early Devonian; however, only a small fraction of this diversity has been formally described and critically evaluated. • Methods Thin sections, previously prepared by grinding wafers of chert from the Rhynie beds, were studied by transmitted light microscopy. Fossils corresponding to the description of Archaeospora spp. occurred in 29 slides, and were measured, photographed and compared with modern-day species in that genus. • Key Results Sessile propagules <85 µm in diameter, some still attached to a sporiferous saccule, were found in early land plant axes and the chert matrix; they developed, in a similar manner to extant Archaeospora, laterally or centrally within the saccule neck. Microscopic examination and comparison with extant fungi showed that, morphologically, the fossils share the characters used to circumscribe the genus Archaeospora (Glomeromycota; Archaeosporales; Archaeosporaceae). • Conclusions The fossils can be assigned with confidence to the extant family Archaeosporaceae, but because molecular analysis is necessary to place organisms in these taxa to present-day genera and species, they are placed in a newly proposed fossil taxon, Archaeosporites rhyniensis.
Photoautotrophic microorganisms were likely abundant in the Early Devonian Rhynie ecosystem;howev... more Photoautotrophic microorganisms were likely abundant in the Early Devonian Rhynie ecosystem;however, documented evidence of these life forms is rare. Hagenococcus aggregatus nov. gen. et sp. occurs in the Rhynie chert matrix as solitary cells, dyads, triads, linear, decussate, and isobilateral tetrads, sarcinoid packets, short filaments, irregular aggregations, and colonies. Individual cells are 15-40(->55) mu m in diameter. While it cannot be ruled out that H. aggregatus is a large cyanobacterium, affinities to the Chlorophyta or Streptophyta are far more likely. Some of the cells contain a prominent, spheroid inclusion which might represent the pyrenoid. Hagenococcus aggregatus expands our knowledge of the diversity of primary producers in Paleozoic non-marine ecosystems.
The impact of the variations in the chemical composition of higher vascular plant cuticles on the... more The impact of the variations in the chemical composition of higher vascular plant cuticles on their fossil record is usually not considered in paleobotanical and, more particularly, taphonomic studies. Here we address the subject with reference to the chemical characterization of insoluble cuticular matrices of a large variety of recent and fossil cuticles. The cuticles were analyzed using Curie-point pyrolysis-gas chromatographic techniques. Cuticular matrices of extant higher plants consist either of the biopolyester cutin, the insoluble, non-hydrolyzable polymethylenic biopolymer cutan, or a mixture of both biopolymers. In fossil cuticles an additional cuticular matrix type consisting of cutan and cutin-derived material is recognized. On the basis of the variations in their chemical composition and the different behavior of the cuticular constituents (viz., cutin and cutan) during diagenesis, it is concluded that the paleobotanical record of cuticles will be biased toward taxa originally having a significant amount of cutan in their cuticular matrix.
Starch is a major component in the human diet, and the acquisition of starch-rich food sources is... more Starch is a major component in the human diet, and the acquisition of starch-rich food sources is considered a pivotal step in the biological and cultural evolution of humankind. However, the potential role of starch as an energy vector in paleo-ecosystems has never been addressed, obviously due to the lack of tangible records of preQuaternary starch grains. Here we describe similar to 280-m. y.-old lycopsid megaspores from Permian forest-swamp deposits in north China that bear caps of granular material. Size, shape, and surface structures as well as chemical and optical properties of these grains show that these caps are masses of compound storage starch. This is by far the oldest unequivocal record of fossil starch known to date. Deposition outside the actual megaspore container makes it unlikely that these starches were used for embryo nutrition; moreover, ultrathin sections of the megaspores indicate that they may have been produced after the megaspores were fertilized. By analogy to the elaiosomes on seeds of zoochorous plants today, we suggest that these starch caps were used to attract and reward animals, possibly land arthropods or snails, for megaspore dispersal. This study offers a rare glimpse into early stages of plant-animal co-evolution in Permian swamp-forest ecosystems.
Comptes rendus de l'Académie des sciences. Série 2. Sciences de la terre et des planètes, Apr 1, 1998
Three different types of climbing organs of seed ferns are reported from the Upper Stephanian (Cp... more Three different types of climbing organs of seed ferns are reported from the Upper Stephanian (Cppermost Carboniferous) of central France on the basis of cuticular material. These three types are climber hooks, tendrils and branched tendrils terminating in adhesive discs. All are very similar to climbing organs of modern angiosperms. These discoveries demonstrate the potential of cuticulal analysis for the reconstruction of growth habits of fossil plants. Moreover, they exemplify that climbing and scrambling were common life strategies among Late Carboniferous seed ferns. The increasing proportion of climbing seed ferns in the Stephanian is interpreted as an expression of changing community structures of Late Palaeozoic coal swamp forests. C Academic de sciences / Elsevier, Paris.
Palaeogeography, Palaeoclimatology, Palaeoecology, Oct 1, 2019
Palynological assemblages from the Tulong succession in South Tibet enabled the recognition of th... more Palynological assemblages from the Tulong succession in South Tibet enabled the recognition of three miospore biozones within the Zhangdong and 'Yali' formations. In ascending order, they are the Retispora lepidophyta-Verrucosisporites nitidus (LN) Biozone, the Vallatisporites vallatus-Foveosporites pellucidus (VP) Biozone and the Rugospora polyptycha-Tricidarisporites arcuatus (PA) Biozone. The LN Biozone in the Tulong section can be correlated to the LN Biozone of Western Europe, based on
This paper provides the first description of the cuticles ofLescuropteris genuina, a pteridosperm... more This paper provides the first description of the cuticles ofLescuropteris genuina, a pteridosperm from the Upper Stephanian of the Blanzy-Montceau Basin, Central France. The status of the genusLescuropteris, which is often compared withOdontopteris, is discussed. However, cuticles seem to justify a separate status. Of special interest is the discovery of a modified pinna terminal with well developed tendrils, providing evidence
Fungi today enter into relationships with other fungi in many ways. Although this was likely also... more Fungi today enter into relationships with other fungi in many ways. Although this was likely also the case in the geologic past, detailed descriptions of interfungal associations and interactions based on fossils remain scarce. Sporocarps bounded by a peridium-like envelope occur singly within the lumen of large glomeromycotan spores (Palaeomyces gordonii var. major) from the Lower Devonian Rhynie chert. The envelope consists of multi-branched, interlacing hyphae. At the tips of hyphae, extending from the envelope into the lumen are produced spheroidal to urn-shaped spores. Similar sporocarps are found in several present day species in the Glomeraceae. Clusters of spores, superficially resembling sporocarps, may also
The growth habit of the Late Carboniferous-Early Permian pteridosperm Pseudomariopteris busquetii... more The growth habit of the Late Carboniferous-Early Permian pteridosperm Pseudomariopteris busquetii is reconstructed based on compression material from the upper Stephanian of the Blanzy-Montceau and Commentry Basins (Massif Central, France), and the upper Rotliegend of the Saar-Nahe Basin (Nahe Group, N 4, Rheinland Pfalz, Germany). Pseudomariopteris busquetii was a medium-sized, vine- to liana-like plant with slender stems to which small bipartite fronds were attached. What is most interesting is that the species used at least two different strategies to both anchor and support the plant body. Most specimens possess specialized climber hooks developed from apical extensions of the pinna axes, indicating that the fronds were used to attach the plant. A few specimens suggest that the stem may also have had some capacity for attachment. In the absence of suitable supports, however, P. busquetii was apparently able to grow in dense stands or thickets in which the individual plants supported each other.
Review of Palaeobotany and Palynology, Mar 1, 2007
The Carnian flora from Lunz (Lower Austria) ranks among the richest and most diverse fossil flora... more The Carnian flora from Lunz (Lower Austria) ranks among the richest and most diverse fossil floras from the Upper Triassic. It is one of the first modern Triassic floras with bennettitaleans. Although this flora is often referred to in the literature, modern taxonomic studies are mostly absent; only some of the reproductive structures have been studied in detail. Many of the plant remains yield excellently preserved cuticles. During a systematic study of the Pterophyllum leaves from Lunz, it appeared that several species previously ...
Review of Palaeobotany and Palynology, Feb 1, 2010
The Bennettitales are a Mesozoic group of gymnosperms with complex reproductive organs that figur... more The Bennettitales are a Mesozoic group of gymnosperms with complex reproductive organs that figure prominently in hypotheses on the ancestry and origin of angiosperms. However, the exact phylogenetic position of the Bennettitales is still debated, due in part to the scarcity of conclusive fertile remains from the Triassic. In this study we reconstruct a bennettitalean flower from isolated parts from the Carnian (Upper Triassic) of Lunz in Lower Austria, including Cycadolepis wettsteinii scale leaves, Haitingeria krasseri pollen organs, and Bennetticarpus wettsteinii ovulate organs/seed cones, based on correspondences in gross morphology and epidermal anatomy. The flower has small pollen organs with spreading and well-exposed pollen sacs; pollen sacs are not organised in synangia, and the ovulate organ is characterised by a low number of relatively large seeds and a large number of interseminal scales in relation to ovules/seeds. The flower lacks several of the characteristic features seen in geologically younger bennettitaleans, including fused, inwardly curved pollen organs and large number of small seeds. The association of these isolated organs to a single flower provides a rare opportunity to assess the attribution of these early representative of the Bennettitales, and sheds new light on the evolutionary history and phylogenetic position of this ancient group of seed plants.
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