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41-933: The Westphalian is preceded by the Namurian Stage/Age (which corresponds to the Millstone Grit Series of Great Britain) and succeeded by the Stephanian Stage/Age (which corresponds to the uppermost part of the Coal Measures of Great Britain). In the official geologic time scale of the International Commission on Stratigraphy (ICS ), the Westphalian is placed within the Pennsylvanian Subsystem/Subperiod (323-299 Ma) of

82-542: A few coalfields, such as the Nord-Pas-des-Calais basin of northern France, the decline is delayed until the mid-Bolsovian, while in other areas it may begin as early as the late Duckmantian. The overall downward diversity trend is slight, but several notable lycopsid and sphenopsid species disappear from European coal swamps at this time. Westphalian D is often referred to as the Asturian , named after

123-595: A modified shoot system acting as roots, bipolar and secondary growth , and an upright stance. The remains of Lepidodendron lycopods formed many fossil coal deposits. In Fossil Grove , Victoria Park, Glasgow, Scotland, fossilized lycophytes can be found in sandstone . The Lycopodiopsida had their maximum diversity in the Pennsylvanian (Upper Carboniferous), particularly tree-like Lepidodendron and Sigillaria that dominated tropical wetlands. The complex ecology of these tropical rainforests collapsed during

164-928: A number of extinct orders in their division (phylum) Lycophyta, although they differ on the placement of some genera. The orders included by Taylor et al. are: Mauseth uses the order †Asteroxylales, placing Baragwanathia in the Protolepidodendrales. The relationship between some of these extinct groups and the extant ones was investigated by Kenrick and Crane in 1997. When the genera they used are assigned to orders, their suggested relationship is: †Drepanophycales († Asteroxylon , † Baragwanathia , † Drepanophycus ) Lycopodiales †Protolepidodendrales († Leclercqia , † Minarodendron ) Selaginellales ( Selaginella , including subg. Stachygynandrum and subg. Tetragonostachys ) Isoetales ( Isoetes ) †Lepidodendrales († Paralycopodites ) The Lycopodiopsida are distinguished from other vascular plants by

205-538: A size limit on the genome, we find the largest known genomes in the clade in Isoetes , as multiflagellated sperm is not exposed for the same selection pressure as biflagellate sperm in regard of size. The extant lycophytes are vascular plants (tracheophytes) with microphyllous leaves , distinguishing them from the euphyllophytes (plants with megaphyllous leaves ). The sister group of the extant lycophytes and their closest extinct relatives are generally believed to be

246-750: A whole) are uncommon in the following "Cantabrian" substage of the Stephanian Stage. The end of the Asturian is a topic of strong debate; most estimates place the Westphalian-Stephanian boundary before the start of the Kasimovian global stage (~307 Ma), whereas a few place the boundary within the Kasimovian. U-Pb radiometric dating of tonstein beds in Spain estimate that the Asturian lasted from 310.7 to 307.5 Ma, ending just prior to

287-619: Is a subdivision of the Carboniferous system or period , as well as the regional Silesian series . The Namurian is named for the Belgian city and province of Namur where strata of this age occur (part of the Belgian Coal Measures ). The Millstone Grit Group in the lithostratigraphy of northern England and parts of Wales is also of Namurian age. The Namurian age lasted from 331 to 319 million years ago. It

328-606: Is an endophytic fungus present in Huperzia serrata that produces Huperzine A , a biomedical compound which has been approved as a drug in China and a dietary supplement in the U.S. to treat Alzheimer's Disease. This fungal endophyte can be cultivated much more easily and on a much larger scale than H. serrata itself which could increase the availability of Huperzine A as a medicine. The spores of lycopods are highly flammable and so have been used in fireworks . Lycopodium powder ,

369-601: Is named after the village of Duckmanton in Derbyshire , England. The base of the Duckmantian is defined by the ammonoid Anthracoceratites vaderbeckei . The boundary between the global Bashkirian and Moscovian stages (~315.2 Ma) corresponds to the mid-late part of the Duckmantian. The lower-middle part of the Duckmantian corresponds to the Lonchopteris rugosa Assemblage-zone, the most diverse plant biozone in

410-728: Is preceded by the Visean stage/age (which corresponds to the upper Carboniferous Limestone of Great Britain) and succeeded by the Westphalian stage/age (which corresponds to the lower and middle Coal Measures of Great Britain). In the official geologic timescale of the International Commission on Stratigraphy (ICS), the Namurian straddles the boundary between the Mississippian subperiod (359-323 Ma) and

451-544: The Calymmotheca ("Lyginopteris") hoeninghausii assemblage zone. Many widespread plant species first appear near the base of the Langsettian, indicating a spike of diversification in tropical coal swamp habitats. Plant diversity steadily increases through the entire Langsettian, though this may be a result of ecological factors such as the receding coastline. The Duckmantian , previously known as Westphalian B ,

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492-478: The Asturias region of northwest Spain . In most of Europe, Westphalian D is distinguished by plant fossils. Asturias is one of the few European regions with enough late Westphalian marine fossils to allow for precise correlations with other marine strata. The proposal to fully implement the name "Asturian" has yet to be ratified, as some stratigraphic difficulties in Spain are not fully resolved. The lower part of

533-771: The Induan (earliest Triassic), particularly Pleuromeia . After the worldwide Permian–Triassic extinction event , members of this group pioneered the repopulation of habitats as opportunistic plants. The heterogeneity of the terrestrial plant communities increased markedly during the Middle Triassic when plant groups like horsetails, ferns, pteridosperms , cycads , ginkgos and conifers resurfaced and diversified quickly. Lycophytes form associations with microbes such as fungi and bacteria, including arbuscular mycorrhizal and endophytic associations. Arbuscular mycorrhizal associations have been characterized in all stages of

574-545: The Maritime Provinces of Canada. The Langsettian , previously known as Westphalian A , is named after the village of Langsett in South Yorkshire , England. It marks the base of the Westphalian regional stage, as defined by the ammonoid Gastrioceras subcrenatum . The base of the Langsettian (and the Westphalian as a whole) has been dated to around 319.9 or 319.2 Ma. The Langsettian corresponds to

615-433: The Pennsylvanian subperiod (323-299 Ma). The upper part of the (regionally defined) Namurian stage corresponds to the (internationally used) Bashkirian stage whilst the lower part is assigned to the preceding Serpukhovian stage. Frequent references appear in scientific literature to a Namurian epoch or Namurian series , reflecting the stage's earlier status. Substages, from youngest to oldest: The boundary between

656-454: The zosterophylls , a paraphyletic or plesion group. Ignoring some smaller extinct taxa, the evolutionary relationships are as shown below.  (multiple branches, incertae sedis )  living lycophytes and  their extinct close relatives   ferns & horsetails   spermatophytes  (seed plants) As of 2019 , there was broad agreement, supported by both molecular and morphological evidence, that

697-592: The zosterophylls . For example, Kenrick & Crane (1997) use the subdivision Lycophytina for this purpose, with all extant lycophytes falling within the class Lycopsida. Other sources exclude the zosterophylls from any "lycophyte" taxon. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the three orders are placed in a single class, Lycopodiopsida, holding all extant lycophyte species. Older systems have used either three classes, one for each order, or two classes, recognizing

738-461: The Asturian belongs to the Linopteris obliqua assemblage zone (sometimes termed the Linopteris bunburii zone). This biozone is notably lower in diversity than previous Westphalian biozones. Plant fossils are still common over much of Europe, with Neuropteris ovata as a particularly abundant species. An important ecological turnover occurs about halfway through the Asturian (~309 Ma), with

779-769: The Carboniferous System/Period. As a regionally defined stage, the Westphalian overlaps with official ICS stages which are in use on an international level. The Westphalian extends from the approximately the upper half of the Bashkirian Stage through the Moscovian Stage, and possibly includes a small portion of the Kasimovian Stage. Many older scientific sources refer to the Westphalian as an epoch or series, which are higher geological ranks than its current status. Since 1935,

820-524: The Carboniferous coalfields of Europe. The rising diversity trend of the Langsettian continues into this biozone, with few notable changes in species composition. In the majority of European coalfields, plant diversity reached a plateau around halfway through the Duckmantian. Coal swamps became increasingly unstable in the Paripteris linguaefolia assemblage zone, which begins in the upper part of

861-533: The Duckmantian. The Bolsovian , previously known as Westphalian C , is named after the town of Bolsover in Derbyshire. The base of the Bolsovian is defined by the ammonoid Donetzoceras aegiranum , and has an estimated age of around 313.8 or 313.7 Ma. The Paripteris linguaefolia assemblage zone continues into the Bolsovian, and a decline in plant diversity is apparent across the entirety of Europe. In

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902-402: The Kasimovian. The Westphalian interval is widely recognized for its coal deposits-- rocks that were deposited broadly across regions that were in low paleolatitudes. These deposits, from so-called "coal swamps" have yielded rich assemblages of fossils including spore-bearing and seed-bearing plants, fishes, and tetrapods. Amphibians were diverse and dominated some communities. The collapse of

943-687: The Lycopodiopsida first appear in the Silurian period, along with a number of other vascular plants. The Silurian Baragwanathia longifolia is one of the earliest identifiable species. Lycopodolica is another Silurian genus which appears to be an early member of this group. The group evolved roots independently from the rest of the vascular plants. From the Devonian onwards, some species grew large and tree-like. Devonian fossil lycopsids from Svalbard , growing in equatorial regions, raise

984-679: The Middle Pennsylvanian due to a change in climate. In Euramerica , tree-like species apparently became extinct in the Late Pennsylvanian, as a result of a transition to a much drier climate, giving way to conifers , ferns and horsetails . In Cathaysia (now South China), tree-like species survived into the Permian . Nevertheless, lycopodiopsids are rare in the Lopingian (latest Permian), but regained dominance in

1025-530: The PPG ;I system, the class is divided into three orders, Lycopodiales , Isoetales and Selaginellales . Club-mosses (Lycopodiales) are homosporous, but the genera Selaginella (spikemosses) and Isoetes (quillworts) are heterosporous, with female spores larger than the male. As a result of fertilisation, the female gametophyte produces sporophytes. A few species of Selaginella such as S. apoda and S. rupestris are also viviparous ;

1066-505: The Westphalian has been split into four substages, from oldest to youngest: Langsettian (Westphalian A), Duckmantian (Westphalian B), Bolsovian (Westphalian C), and "Asturian" (Westphalian D). These substages are defined by guide fossils, or "index fossils ," particularly plant macrofossils , miospores , and ammonoids . The Westphalian exhibits distinctive changes in plant diversity, and many plant macrofossil assemblage zones have been defined across an area encompassing Europe, Turkey , and

1107-646: The arrival of the Crenulopteris acadica assemblage zone (previously known as the Lobatopteris vestita zone). Lycopsid fossils become very rare, while marattialean ferns become abundant in coal swamp deposits. Many European coalfields were positioned in a foreland basin north of the Variscan orogeny . As mountain-building continued, uplift accelerated in the basin, endangering the survival of coal swamp environments. Plant fossils (and coal deposits as

1148-419: The class are also called clubmosses , firmosses , spikemosses and quillworts . They have dichotomously branching stems bearing simple leaves called microphylls and reproduce by means of spores borne in sporangia on the sides of the stems at the bases of the leaves. Although living species are small, during the Carboniferous , extinct tree-like forms ( Lepidodendrales ) formed huge forests that dominated

1189-616: The closer relationship between Isoetales and Selaginellales. In these cases, a higher ranked taxon is needed to contain the classes (see Table 1). As Table 2 shows, the names "Lycopodiopsida" and "Isoetopsida" are both ambiguous. The PPG I system divides up the extant lycophytes as shown below. Some extinct groups, such as zosterophylls , fall outside the limits of the taxon as defined by the classifications in Table 1 above. However, other extinct groups fall within some circumscriptions of this taxon. Taylor et al. (2009) and Mauseth (2014) include

1230-422: The extant lycophytes fell into three groups, treated as orders in PPG I, and that these, both together and individually, are monophyletic , being related as shown in the cladogram below:   lycopodiales     Isoetales   Selaginellales The rank and name used for the taxon holding the extant lycophytes (and their closest extinct relatives) varies widely. Table 1 below shows some of

1271-414: The gametophyte develops on the mother plant, and only when the sporophyte's primary shoot and root is developed enough for independence is the new plant dropped to the ground. Many club-moss gametophytes are mycoheterotrophic and long-lived, residing underground for several years before emerging from the ground and progressing to the sporophyte stage. Lycopodiaceae and spikemosses ( Selaginella ) are

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1312-592: The global Serpukhovian and Bashkirian stages (and thus the Mississippian and Pennsylvanian subperiods) occurs within the Chokierian substage. This geochronology article is a stub . You can help Misplaced Pages by expanding it . This article about stratigraphy is a stub . You can help Misplaced Pages by expanding it . Lycopsid See Table 1 . Lycopodiopsida is a class of vascular plants also known as lycopods or lycophytes . Members of

1353-435: The highest ranks that have been used. Systems may use taxa at a rank lower than the highest given in the table with the same circumscription; for example, a system that uses Lycopodiophyta as the highest ranked taxon may place all of its members in a single subclass. Some systems use a higher rank for a more broadly defined taxon of lycophytes that includes some extinct groups more distantly related to extant lycophytes, such as

1394-523: The landscape and contributed to coal deposits. The nomenclature and classification of plants with microphylls varies substantially among authors. A consensus classification for extant (living) species was produced in 2016 by the Pteridophyte Phylogeny Group (PPG I), which places them all in the class Lycopodiopsida, which includes the classes Isoetopsida and Selaginellopsida used in other systems. (See Table 2 .) Alternative classification systems have used ranks from division (phylum) to subclass. In

1435-683: The lycophyte lifecycle: mycoheterotrophic gametophyte, photosynthetic surface-dwelling gametophyte, young sporophyte, and mature sporophyte. Arbuscular mycorrhizae have been found in Selaginella spp. roots and vesicles. During the mycoheterotrophic gametophyte lifecycle stage, lycophytes gain all of their carbon from subterranean glomalean fungi. In other plant taxa, glomalean networks transfer carbon from neighboring plants to mycoheterotrophic gametophytes. Something similar could be occurring in Huperzia hypogeae gametophytes which associate with

1476-442: The only vascular plants with biflagellate sperm, an ancestral trait in land plants otherwise only seen in bryophytes . The only exceptions are Isoetes and Phylloglossum , which independently has evolved multiflagellated sperm cells with approximately 20 flagella (sperm flagella in other vascular plants can count at least thousand, but is completely absent in seed plants except for Ginkgo and cycads). Because only two flagella puts

1517-430: The plant grew, leaving only a small cluster of leaves at the top. The lycopsids had distinctive features such as Lepidodendron lycophytes, which were marked with diamond-shaped scars where they once had leaves. Quillworts (order Isoetales) and Selaginella are considered their closest extant relatives and share some unusual features with these fossil lycopods, including the development of both bark, cambium and wood ,

1558-489: The possession of microphylls and by their sporangia, which are lateral as opposed to terminal and which open (dehisce) transversely rather than longitudinally. In some groups, the sporangia are borne on sporophylls that are clustered into strobili. Phylogenetic analysis shows the group branching off at the base of the evolution of vascular plants and they have a long evolutionary history. Fossils are abundant worldwide, especially in coal deposits . Fossils that can be ascribed to

1599-455: The possibility that they drew down enough carbon dioxide to change the Earth's climate significantly. During the Carboniferous , tree-like plants (such as Lepidodendron , Sigillaria , and other extinct genera of the order Lepidodendrales ) formed huge forests that dominated the landscape. Unlike modern trees, leaves grew out of the entire surface of the trunk and branches, but fell off as

1640-556: The rainforest ecology between the Moscovian and Kasimovian removed many amphibian species that did not survive as well in the cooler, drier conditions. Reptiles, however prospered due to specific key adaptations and underwent a major evolutionary radiation, in response to the drier climate that led to the rainforest collapse. Namurian The Namurian is a stage in the regional stratigraphy of northwest Europe, with an age between roughly 331 and 319 Ma (million years ago) . It

1681-552: The same glomalean phenotypes as nearby Huperzia hypogeae sporophytes. Fungal endophytes have been found in many species of lycophyte, however the function of these endophytes in host plant biology is not known. Endophytes of other plant taxa perform roles such as improving plant competitive fitness, conferring biotic and abiotic stress tolerance, promoting plant growth through phytohormone production or production of limiting nutrients. However, some endophytic fungi in lycophytes do produce medically relevant compounds. Shiraia sp Slf14

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