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Archaeopteris Macilenta
''Archaeopteris macilenta'' is distinguished from other species of the genus by leaves which are divided into narrow segments at their tips. Sporangia were borne on different parts of the branches with ordinary foliage leaves. ''Archaeopteris macilenta'' leaves and fertile shoots are attached to wood which when Permineralization, permineralized is called ''Callixylon newberryi''. ''Archaeopteris'' is retained in the Class (biology), class Progymnosperm, Progymnospermopsida which includes plants with gymnospermous anatomy and pteridophytic reproduction. History Fossilized remains of the ''Archaeopteris macilenta'' were initially discovered in 1958 the continental beds from the upper Devonian in eastern New York and have since been located in other floodplain localities from the Catskill Delta. It is often referred to as one of the earliest true ferns which bears significance. ''Archaeopteris'' made up 90% of the forests during the late Devonian which accelerated the increase of o ... [...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] |
