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34-564: Emplectopteridaceae is an extinct family of pteridosperms ("seed ferns") known mainly from Permian floras of the Cathaysian Realm (corresponding to modern East Asia ). They were mostly shrubby plants with a scrambling or upright habit, and favoured a range of habitats from arid to moist or even aquatic. The foliage is the most abundant known remains of this family, having been reported from Artinskian to Wuchiapingian macrofloras of both north and south China . Their venation

68-402: A Permian plant is a stub . You can help Misplaced Pages by expanding it . Pteridosperms Pteridospermatopsida Pteridospermatophyta , also called " pteridosperms " or " seed ferns " are a polyphyletic grouping of extinct seed-producing plants . The earliest fossil evidence for plants of this type are the lyginopterids of late Devonian age. They flourished particularly during

102-567: A particular state of preservation to be placed in organ-genera. In addition, a small subset of organ-genera, to be known as form-genera, were recognised based on the artificial taxa introduced by Brongniart mainly for foliage fossils. The concepts and regulations surrounding organ- and form-genera were modified within successive codes of nomenclature, reflecting a failure of the paleobotanical community to agree on how this aspect of plant taxonomic nomenclature should work (a history reviewed by Cleal and Thomas in 2020 ). The use of organ- and fossil-genera

136-401: A plant that has long since died. Such fossils may be prehistoric impressions that are many millions of years old, or bits of charcoal that are only a few hundred years old. Prehistoric plants are various groups of plants that lived before recorded history (before about 3500 BC ). Plant fossils can be preserved in a variety of ways, each of which can give different types of information about

170-529: A wealth of fossils containing arborescent lycopods up to 30 m tall, abundant seed plants , such as conifers and seed ferns , and countless smaller, herbaceous plants . Angiosperms ( flowering plants ) evolved during the Mesozoic , and flowering plant pollen and leaves first appeared during the Early Cretaceous , approximately 130 million years ago. A plant fossil is any preserved part of

204-477: Is a similar study to that of paleontology , but paleoecology uses more methodology from the biological sciences and geological sciences rather than from an anthropological standpoint as paleontologists do. Paleopalynology , more commonly known as palynology , is the science and study of ancient palynomorphs: particles sized between 5 and 500 micrometers. This would be an inclusion of pollen and spores and any other micro-organic matter. Paleopalynology

238-504: Is an Early Devonian sinter ( hot spring ) deposit composed primarily of silica . It is exceptional due to its preservation of several different clades of plants, from mosses and lycophytes to more unusual, problematic forms. Many fossil animals, including arthropods and arachnids , are also found in the Rhynie chert, and it offers a unique window into the history of early terrestrial life. Plant-derived macrofossils become abundant in

272-493: Is characteristically flexuous to loosely anastomosed , and rather different from the more regularly anastomosed venation of the true gigantopterids (with which the Emplctopteridaceae fronds used to be confused). The stratigraphically older leaves tended to be twice pinnate ( Emplectopteris ), the later leaves once pinnate or entire ( Gigantonoclea ). The ovules were bilaterally symmetrical and attached to

306-412: Is fundamental to the study of green plant development and evolution . Paleobotany is a historical science much like its adjacent, paleontology. Because of the understanding that paleobotany gives to archeologists, it has become important to the field of archaeology as a whole. primarily for the use of phytoliths in relative dating and in paleoethnobotany . The study and discipline of paleobotany

340-408: Is normally lost during fossilization. Plant remains can be preserved in a variety of ways, each revealing different features of the original parent plant. Because of this, paleobotanists usually assign different taxonomic names to different parts of the plant in different modes of preservation. For instance, in the subarborescent Palaeozoic sphenophytes , an impression of a leaf might be assigned to

374-704: Is simply paleobotany on a much smaller scale, the two in close association with each other. Similar to paleobotany, we can tell a great deal of information about the environment and biome at the time these particles existed prehistorically. These particles also help geologists identify and date the rock strata of sedimentary rocks . It is also used to find natural oils and gas within these rock layers for extraction . Besides uncovering documentation of our past environmental conditions, palynology can also tell us about animal diets, historical standings of human allergies , and reveal evidence in crime cases. Macroscopic remains of true vascular plants are first found in

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408-654: The Carboniferous and Permian periods. Pteridosperms declined during the Mesozoic Era and had mostly disappeared by the end of the Cretaceous Period, though Komlopteris seem to have survived into Eocene times, based on fossil finds in Tasmania . With regard to the enduring utility of this division , many palaeobotanists still use the pteridosperm grouping in an informal sense to refer to

442-546: The Petriellales , Corystospermales and Caytoniales . Their discovery attracted considerable attention at the time, as the pteridosperms were the first extinct group of vascular plants to be identified solely from the fossil record. In the 19th century the Carboniferous Period was often referred to as the "Age of Ferns" but these discoveries during the first decade of the 20th century made it clear that

476-534: The "Age of Pteridosperms" was perhaps a better description. During the 20th century the concept of pteridosperms was expanded to include various Mesozoic groups of seed plants with fern-like fronds, such as the Corystospermaceae . Some palaeobotanists also included seed plant groups with entire leaves such as the Glossopteridales and Gigantopteridales , which was stretching the concept. In

510-541: The Late Devonian including tree trunks, fronds , and roots . The earliest tree was once thought to be Archaeopteris , which bears simple, fern -like leaves spirally arranged on branches atop a conifer -like trunk , although it is now known to be the recently discovered Wattieza . Widespread coal swamp deposits across North America and Europe during the Carboniferous Period contain

544-449: The ancestry of flowering plants (angiosperms). A 2009 study concluded that " phylogenetic analysis techniques have surpassed the hard data needed to formulate meaningful phylogenetic hypotheses" regarding the relationships of "seed ferns" to living plant groups. Palaeobotany Paleobotany is important in the reconstruction of ancient ecological systems and climate , known as paleoecology and paleoclimatology respectively. It

578-539: The context of modern phylogenetic models, the groups often referred to as pteridosperms appear to be liberally spread across a range of clades, and many palaeobotanists today would regard pteridosperms as little more than a paraphyletic 'grade-group' with no common lineage. One of the few characters that may unify the group is that the ovules were borne in a cupule , a group of enclosing branches, but this has not been confirmed for all "pteridosperm" groups. It has been speculated that some seed fern groups may be close to

612-500: The critical discovery that some of these fronds (genus Lyginopteris ) were associated with seeds (genus Lagenostoma ) that had identical and very distinctive glandular hairs, and concluded that both fronds and seeds belonged to the same plant. Soon, additional evidence came to light suggesting that seeds were also attached to the Carboniferous fern-like fronds Dicksonites , Neuropteris and Aneimites . Initially it

646-465: The earth’s timeline. Paleobotany also succeeded in the hands of German paleontologist Ernst Friedrich von Schlothiem , and Czech nobleman and scholar, Kaspar Maria von Sternberg . As paleobotany is the specification of fossilized plant life and the environment in which they thrived in, paleoecology is the study of all once-living organisms and the interactions held in the environments they once existed in, before becoming extinct . Paleoecology

680-489: The form and position of attachment of the ovules strongly suggests affinities with the callistophytaleans . Emplectopterids have only reliably been reported from China. Gigantonoclea -like leaves have also been reported from Permian macrofloras of North America , but without any evidence of reproductive structures, and the affinity of these leaves may lie nearer to the Peltaspermales . This article related to

714-788: The fossil record during the Silurian Period of the Paleozoic era. Some dispersed, fragmentary fossils of disputed affinity, primarily spores and cuticles , have been found in rocks from the Ordovician Period in Oman , and are thought to derive from liverwort - or moss -grade fossil plants. An important early land plant fossil locality is the Rhynie chert , found outside the village of Rhynie in Scotland . The Rhynie chert

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748-473: The genus Annularia , a compression of a cone assigned to Palaeostachya , and the stem assigned to either Calamites or Arthroxylon depending on whether it is preserved as a cast or a petrifaction. All of these fossils may have originated from the same parent plant but they are each given their own taxonomic name. This approach to naming plant fossils originated with the work of Adolphe-Théodore Brongniart . For many years this approach to naming plant fossils

782-534: The modern-day seed plants, the cycads . In 1899 the German palaeobotanist Henry Potonié coined the term " Cycadofilices " ("cycad-ferns") for such fossils, suggesting that they were a group of non-seed plants intermediate between the ferns and cycads. Shortly afterwards, the British palaeobotanists Frank Oliver and Dukinfield Henry Scott (with the assistance of Oliver's student at the time, Marie Stopes ) made

816-413: The original parent plant. These modes of preservation may be summarised in a paleobotanical context as follows. Plant fossils almost always represent disarticulated parts of plants; even small herbaceous plants are rarely preserved whole. The few examples of plant fossils that appear to be the remains of whole plants are in fact incomplete as the internal cellular tissue and fine micromorphological detail

850-418: The same species. It appeared that morphotaxa offered no real advantage to paleobotanists over normal fossil-taxa and the concept was abandoned with the 2011 botanical congress and the 2012 International Code of Nomenclature for algae, fungi, and plants . Some plants have remained almost unchanged throughout earth's geological time scale. Horsetails had evolved by the Late Devonian, early ferns had evolved by

884-412: The seed plants that are not angiosperms , coniferoids ( conifers or cordaites ), ginkgophytes or cycadophytes (cycads or bennettites ). This is particularly useful for extinct seed plant groups whose systematic relationships remain speculative, as they can be classified as pteridosperms with no valid implications being made as to their systematic affinities. Also, from a purely curatorial perspective

918-435: The taxon) is defined by the taxonomist who uses the name. Such a change in circumscription could result in an expansion of the range of plant parts or preservation states that could be incorporated within the taxon. For instance, a fossil-genus originally based on compressions of ovules could be used to include the multi-ovulate cupules within which the ovules were originally borne. A complication can arise if, in this case, there

952-400: The term pteridosperms is a useful shorthand for describing the fern-like fronds that were probably produced by seed plants, which are commonly found in many Palaeozoic and Mesozoic fossil floras. The concept of pteridosperms goes back to the late 19th century when palaeobotanists came to realise that many Carboniferous fossils resembling fern fronds had anatomical features more reminiscent of

986-441: The underside of the leaves / fronds that did not differ significantly from normal vegetative foliage Pollen organs were a complex of filiform microsporophylls each bearing 2-8 sporangia (assigned to the fossil-genus Jiaochengia ). The family is currently only known from adpressions (compression-impressions), and the consequential paucity of anatomical evidence has resulted in some disagreement as to its affinities. However,

1020-530: Was abandoned with the St Louis Code , and replaced by "morphotaxa". The situation in the Vienna Code of 2005 was that any plant taxon whose type is a fossil, except diatoms , can be described as a morphotaxon , a particular part of a plant preserved in a particular way. Although the name is always fixed to the type specimen, the circumscription (i.e. range of specimens that may be included within

1054-470: Was accepted by paleobotanists but not formalised within the International Rules of Botanical Nomenclature . Eventually, Thomas (1935) and Jongmans, Halle & Gothan (1935) proposed a set of formal provisions, the essence of which was introduced into the 1952 International Code of Botanical Nomenclature . These early provisions allowed fossils representing particular parts of plants in

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1088-415: Was an already named fossil-genus for these cupules. If paleobotanists were confident that the type of the ovule fossil-genus and of the cupule fossil-genus could be included in the same genus, then the two names would compete as to being the correct one for the newly emended genus. In general, there would be competing priority whenever plant parts that had been given different names were discovered to belong to

1122-421: Was seen as far back as the 19th century. Known as the “Father of Paleobotany”, French botanist Adolphe-Theodore Brongniart was a sufficient figure in this emergence of Paleobotany, known for his work on the relationship between the living and extinct plant life. This work not only progressed paleobotany but also the understanding of the earth and its longevity in actuality and the organic matter that existed over

1156-626: Was still thought that they were " transitional fossils " intermediate between the ferns and cycads, and especially in the English-speaking world they were referred to as "seed ferns" or "pteridosperms". Today, despite being regarded by most palaeobotanists as only distantly related to ferns, these spurious names have nonetheless established themselves. Nowadays, four orders of Palaeozoic seed plants tend to be referred to as pteridosperms: Lyginopteridales , Medullosales , Callistophytales and Peltaspermales , with "Mesozoic seed ferns" including

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