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Oricilla
''Oricilla'' was a genus of Early Devonian land plant with branching axes. Fossils have been found from the Pragian to the Emsian (). A cladogram published in 2004 by Crane et al. places ''Oricilla'' in the core of a paraphyletic stem group of broadly defined "zosterophylls", basal to the lycopsids (living and extinct clubmosses and relatives). Hao and Xue in 2013 used the absence of terminal sporangia to place the genus in the paraphyletic order Gosslingiales, a group of zosterophylls considered to have indeterminate growth, with fertile branches generally showing circinate vernation (initially curled up). Kenrick and Crane in 1997 also placed the genus in the family Gosslingiaceae, but they place this family in the order Sawdoniales The Sawdoniales are an Order (biology), order or plesion of extinct zosterophylls. The zosterophylls were among the first vascular plants in the fossil record, and share an ancestor with the Lycopodiopsida, living lycophytes. The group has been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zosterophylls
The zosterophylls are a group of extinct land plants that first appeared in the Silurian period. The taxon was first established by Banks in 1968 as the subdivision Zosterophyllophytina; they have since also been treated as the division Zosterophyllophyta or Zosterophyta and the class or plesion Zosterophyllopsida or Zosteropsida. They were among the first vascular plants in the fossil record, and had a world-wide distribution. They were probably stem-group lycophytes, forming a sister group to the ancestors of the living lycophytes. By the late Silurian (late Ludlovian, about ) a diverse assemblage of species existed, examples of which have been found fossilised in what is now Bathurst Island in Arctic Canada. Morphology The stems of zosterophylls were either smooth or covered with small spines known as enations, branched dichotomously, and grew at the ends by unrolling, a process known as circinate vernation. The stems had a central vascular column in which the protoxyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zosterophyll
The zosterophylls are a group of extinct land plants that first appeared in the Silurian period. The taxon was first established by Banks in 1968 as the subdivision Zosterophyllophytina; they have since also been treated as the division Zosterophyllophyta or Zosterophyta and the class or plesion Zosterophyllopsida or Zosteropsida. They were among the first vascular plants in the fossil record, and had a world-wide distribution. They were probably stem-group lycophytes, forming a sister group to the ancestors of the living lycophytes. By the late Silurian (late Ludlovian, about ) a diverse assemblage of species existed, examples of which have been found fossilised in what is now Bathurst Island in Arctic Canada. Morphology The stems of zosterophylls were either smooth or covered with small spines known as enations, branched dichotomously, and grew at the ends by unrolling, a process known as circinate vernation. The stems had a central vascular column in which the protox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gosslingiales
Gosslingiales is an Order (biology), order of extinct zosterophylls. The zosterophylls were among the first vascular plants in the fossil record, and share an ancestor with the Lycopodiopsida, living lycophytes. The group has been divided up in various ways. Hao and Xue in 2013 used the presence or absence of terminal Sporangium, sporangia as a major dividing feature. The order Zosterophyllales was used for species with terminal as well as lateral sporangia, which were considered to have determinate growth, with their sporangia generally being arranged in spikes. The Paraphyly, paraphyletic order Gosslingiales was used for species without terminal sporangia (i.e. with only lateral sporangia), which were considered to have indeterminate growth, with fertile branches generally circinate vernation, circinate (initially curled up). Species assignable to the Gosslingiales made up about 9% of all confirmed species in the Early Devonian flora. Taxonomy Classification Hao and Xue conside ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gosslingiaceae
Gosslingiaceae is a family of extinct zosterophylls. The zosterophylls were among the first vascular plants in the fossil record, and are considered to share an ancestor with the living lycophytes. The family is variously placed in the order Sawdoniales or the order Gosslingiales Gosslingiales is an Order (biology), order of extinct zosterophylls. The zosterophylls were among the first vascular plants in the fossil record, and share an ancestor with the Lycopodiopsida, living lycophytes. The group has been divided up in .... Genera Genera that have been placed in this family by Kenrick and Crane in 1997 and Hao and Xue in 2013 are shown in the table below. References Zosterophylls Prehistoric plant families {{paleobotany-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Devonian
The Early Devonian is the first of three Epoch (geology), epochs comprising the Devonian period, corresponding to the Lower Devonian Series (stratigraphy), series. It lasted from and began with the Lochkovian Stage , which was followed by the Pragian from and then by the Emsian, which lasted until the Middle Devonian began, . During this time, the first Ammonoidea, ammonoids appeared, descending from Bactritida, bactritoid Nautiloidea, nautiloids. Ammonoids during this time period were simple and differed little from their nautiloid counterparts. These ammonoids belong to the order Agoniatitida, which in later epochs evolved to new ammonoid orders, for example Goniatite, Goniatitida and Clymeniida. This class of cephalopod molluscs would dominate the marine fauna until the beginning of the Mesozoic Era. References Early Devonian, Geological epochs Devonian geochronology, *01 {{Geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emsian Life
The Emsian is one of three faunal stages in the Early Devonian Epoch. It lasted from 410.62 ±1.95 million years ago to 393.47 ±0.99 million years ago. It was preceded by the Pragian Stage and followed by the Eifelian Stage. It is named after the Ems river in Germany. The GSSP is located in the Zinzil'ban Gorge in the Kitab State Geological Reserve of Uzbekistan, above the contact with the Madmon Formation. In North America the Emsian Stage is represented by Sawkill or Sawkillian time. Biological events During this period, earliest known Agoniatitida, agoniatitid Ammonoidea, ammonoid fossils began appearing within this stage after first appearing in previous stage and began to evolutionarily radiate within this stage, in which a new ammonoid order Goniatite, Goniatitida rises in the end of Zlichovian stage (Siberian representation; corresponds to early Eifelian and after the end of Early Devonian, before 391.9 Annum, mya). Later agoniatitid ammonoids would die out in the Tag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian Plants
The Devonian ( ) is a geologic period and system of the Paleozoic era during the Phanerozoic eon, spanning 60.3 million years from the end of the preceding Silurian period at million years ago ( Ma), to the beginning of the succeeding Carboniferous period at Ma. It is the fourth period of both the Paleozoic and the Phanerozoic. It is named after Devon, South West England, where rocks from this period were first studied. The first significant evolutionary radiation of life on land occurred during the Devonian, as free- sporing land plants (pteridophytes) began to spread across dry land, forming extensive coal forests which covered the continents. By the middle of the Devonian, several groups of vascular plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants ( pteridospermatophytes) appeared. This rapid evolution and colonization process, which had begun during the Silurian, is known as the Silurian-Devonian Terrestrial Revo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Lycophyte Genera
Prehistory, also called pre-literary history, is the period of human history between the first known use of stone tools by hominins million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared years ago. It took thousands of years for writing systems to be widely adopted, with writing having spread to almost all cultures by the 19th century. The end of prehistory therefore came at different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. It is based on an old conception of history that without written records there could be no history. The most common conception today is that history is based on evidence, however the concept of prehistory hasn't been completely discarded. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sawdoniales
The Sawdoniales are an Order (biology), order or plesion of extinct zosterophylls. The zosterophylls were among the first vascular plants in the fossil record, and share an ancestor with the Lycopodiopsida, living lycophytes. The group has been divided up in various ways. In their major Cladistics, cladistic study of early land plants, Kenrick and Crane placed most of the zosterophylls in the Sawdoniales (which they treated as a plesion). Like other zosterophylls, members of the Sawdoniales bore lateral, reniform sporangia. They branched dichotomously, and grew at the ends by unrolling (vernation, circinate vernation). Some had smooth stems, others were covered in small spines; fungal bodies have been reported in some spines. Taxonomy In 1997, Kenrick and Crane placed most of the zosterophylls in the plesion Sawdoniales, characterizing the group as having "marked bilateral symmetry". Their summary cladogram did not resolve the taxa within the Sawdoniales, other than placing ''Zos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circinate Vernation
Vernation or leafing is the formation of new leaves or fronds. In plant anatomy, it is the arrangement of leaves in a bud. In pine species, new leaves are short and encased in sheaths. Each leaf bundle consists of two to five needles. All the leaves on one section of branch grow in length together. In cabbage species, new leaves are folded over, each covered by the previous leaf. Name The term ''vernation'' is borrowed from New Latin , the act of being verdant or flourishing (). It is cognate with (Latin for " spring") and ("vernal"). Circinate vernation Circinate vernation is the manner in which most fern fronds emerge. As the fern frond is formed, it is tightly curled so that the tender growing tip of the frond (and each subdivision of the frond) is protected within a coil. At this stage it is called a crozier (after the shepherd's crook) or fiddlehead (after the scrollwork at the top of a violin). As the lower parts of the frond expand and toughen up, they begin to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphyly
Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In contrast, a monophyletic grouping (a clade) includes a common ancestor and ''all'' of its descendants. The terms are commonly used in phylogenetics (a subfield of biology) and in the tree model of historical linguistics. Paraphyletic groups are identified by a combination of synapomorphies and symplesiomorphies. If many subgroups are missing from the named group, it is said to be polyparaphyletic. The term received currency during the debates of the 1960s and 1970s accompanying the rise of cladistics, having been coined by zoologist Willi Hennig to apply to well-known taxa like Reptilia (reptiles), which is paraphyletic with respect to birds. Reptilia contains the last common ancestor of reptiles and all descendants of that ancest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pragian
The Pragian is one of three faunal stages in the Early Devonian Epoch. It lasted from 410.8 ± 2.8 million years ago to 407.6 ± 2.8 million years ago. It was preceded by the Lochkovian Stage and followed by the Emsian Stage. The most important Lagerstätte of the Pragian is Rhynie chert in Scotland. It is named after the city of Prague Prague ( ; ) is the capital and List of cities and towns in the Czech Republic, largest city of the Czech Republic and the historical capital of Bohemia. Prague, located on the Vltava River, has a population of about 1.4 million, while its P .... The GSSP is located within the Prague Formation at Velká Chuchle, Prague. In North America the Pragian Stage is represented by Siegenian or Deerparkian time. Pragian life The first ammonoids (order Agoniatitida) appeared in later parts of this stage (at the lower boundary of the Zlichovian stage as it was known in Siberian representations). They were descended from bactritoid nautiloi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
