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Tomiostrobus
''Tomiostrobus'' is an extinct quillwort genus from the Early Triassic of Australia, China and Russia, which was especially widespread in the aftermath of Permian Triassic mass extinctions. Description ''Tomiostrobus australis'' is preserved as whole plants closely spaced within bedding planes, and lived as an early successional weed in lake and pond sedimentary environments, like living ''Isoetes''. Unlike living ''Isoetes'', ''Tomiostrobus'' formed closed cones with sporophylls that were distinctly shouldered and woody. This may have been an adaptation to heavy grazing by herbivorous therapsids. See also * Evolution of plants The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats, through multicellular marine and freshwater green algae, terrestrial bryophytes, lycopods and ferns, to the complex gymnosperms and angiosperms (fl ... References Triassic plants Prehistoric lycophytes Prehistoric lycophyte genera [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomiostrobus Australis
''Tomiostrobus'' is an extinct quillwort genus from the Early Triassic of Australia, China and Russia, which was especially widespread in the aftermath of Permian Triassic mass extinctions. Description ''Tomiostrobus australis'' is preserved as whole plants closely spaced within bedding planes, and lived as an early successional weed in lake and pond sedimentary environments, like living ''Isoetes''. Unlike living ''Isoetes'', ''Tomiostrobus'' formed closed cones with sporophylls that were distinctly shouldered and woody. This may have been an adaptation to heavy grazing by herbivorous therapsids. See also * Evolution of plants References Triassic plants Prehistoric lycophytes Prehistoric lycophyte genera {{triassic-plant-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomiostrobus Polaris
''Tomiostrobus'' is an extinct quillwort genus from the Early Triassic of Australia, China and Russia, which was especially widespread in the aftermath of Permian Triassic mass extinctions. Description ''Tomiostrobus australis'' is preserved as whole plants closely spaced within bedding planes, and lived as an early successional weed in lake and pond sedimentary environments, like living ''Isoetes''. Unlike living ''Isoetes'', ''Tomiostrobus'' formed closed cones with sporophylls that were distinctly shouldered and woody. This may have been an adaptation to heavy grazing by herbivorous therapsids. See also * Evolution of plants The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats, through multicellular marine and freshwater green algae, terrestrial bryophytes, lycopods and ferns, to the complex gymnosperms and angiosperms (f ... References Triassic plants Prehistoric lycophytes Prehistoric lycophyte genera [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomiostrobus Radiatus
''Tomiostrobus'' is an extinct quillwort genus from the Early Triassic of Australia, China and Russia, which was especially widespread in the aftermath of Permian Triassic mass extinctions. Description ''Tomiostrobus australis'' is preserved as whole plants closely spaced within bedding planes, and lived as an early successional weed in lake and pond sedimentary environments, like living ''Isoetes''. Unlike living ''Isoetes'', ''Tomiostrobus'' formed closed cones with sporophylls that were distinctly shouldered and woody. This may have been an adaptation to heavy grazing by herbivorous therapsids. See also * Evolution of plants The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats, through multicellular marine and freshwater green algae, terrestrial bryophytes, lycopods and ferns, to the complex gymnosperms and angiosperms (f ... References Triassic plants Prehistoric lycophytes Prehistoric lycophyte genera [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomiostrobus Sinensis
''Tomiostrobus'' is an extinct quillwort genus from the Early Triassic of Australia, China and Russia, which was especially widespread in the aftermath of Permian Triassic mass extinctions. Description ''Tomiostrobus australis'' is preserved as whole plants closely spaced within bedding planes, and lived as an early successional weed in lake and pond sedimentary environments, like living ''Isoetes''. Unlike living ''Isoetes'', ''Tomiostrobus'' formed closed cones with sporophylls that were distinctly shouldered and woody. This may have been an adaptation to heavy grazing by herbivorous therapsids. See also * Evolution of plants The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats, through multicellular marine and freshwater green algae, terrestrial bryophytes, lycopods and ferns, to the complex gymnosperms and angiosperms (f ... References Triassic plants Prehistoric lycophytes Prehistoric lycophyte genera [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian Triassic
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the sauropsids (reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their amphibian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoetes And Tomiostrobus
''Isoetes'', commonly known as the quillworts, is the only extant genus of plants in the family Isoetaceae, which is in the class of lycopods. There are currently 192 recognized species, with a cosmopolitan distribution but with the individual species often scarce to rare. Some botanists split the genus, separating two South American species into the genus ''Stylites'', although molecular data place these species among other species of ''Isoetes'', so that ''Stylites'' does not warrant taxonomic recognition. Species of ''Isoetes'' virtually identical to modern forms have existed since the Jurassic epoch. The name of the genus may also be spelled ''Isoëtes''. The diaeresis (two dots over the e) indicates that the o and the e are to be pronounced in two distinct syllables. Including this in print is optional; either spelling (''Isoetes'' or ''Isoëtes'') is correct. Description Quillworts are mostly aquatic or semi-aquatic in clear ponds and slow-moving streams, though several ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoetes
''Isoetes'', commonly known as the quillworts, is the only extant genus of plants in the family Isoetaceae, which is in the class of lycopods. There are currently 192 recognized species, with a cosmopolitan distribution but with the individual species often scarce to rare. Some botanists split the genus, separating two South American species into the genus ''Stylites'', although molecular data place these species among other species of ''Isoetes'', so that ''Stylites'' does not warrant taxonomic recognition. Species of ''Isoetes'' virtually identical to modern forms have existed since the Jurassic epoch. The name of the genus may also be spelled ''Isoëtes''. The diaeresis (two dots over the e) indicates that the o and the e are to be pronounced in two distinct syllables. Including this in print is optional; either spelling (''Isoetes'' or ''Isoëtes'') is correct. Description Quillworts are mostly aquatic or semi-aquatic in clear ponds and slow-moving streams, though several ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Therapsid
Therapsida is a major group of eupelycosaurian synapsids that includes mammals, their ancestors and relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more underneath the body, as opposed to the sprawling posture of many reptiles and salamanders. Therapsids evolved from "pelycosaurs", specifically within the Sphenacodontia, more than 279.5 million years ago. They replaced the "pelycosaurs" as the dominant large land animals in the Middle Permian through to the Early Triassic. In the aftermath of the Permian–Triassic extinction event, therapsids declined in relative importance to the rapidly diversifying reptiles during the Middle Triassic. The therapsids include the cynodonts, the group that gave rise to mammals ( Mammaliaformes) in the Late Triassic, around 225 million years ago. Of the non-mammalian therapsids, only cynodonts survived beyond the end of the Triassic, with the only other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolution Of Plants
The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats, through multicellular marine and freshwater green algae, terrestrial bryophytes, lycopods and ferns, to the complex gymnosperms and angiosperms (flowering plants) of today. While many of the earliest groups continue to thrive, as exemplified by red and green algae in marine environments, more recently derived groups have displaced previously ecologically dominant ones; for example, the ascendance of flowering plants over gymnosperms in terrestrial environments. There is evidence that cyanobacteria and multicellular photosynthetic eukaryotes lived in freshwater communities on land as early as 1 billion years ago, and that communities of complex, multicellular photosynthesizing organisms existed on land in the late Precambrian, around . Evidence of the emergence of embryophyte land plants first occurs in the mid-Ordovician (~), and by the middle of the Devonian (~), many of the featur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
