|
Cephalonega
''Cephalonega stepanovi'' is a fossil organism from Ediacaran deposits of the Arkhangelsk Region, Russia. It was described by Mikhail A. Fedonkin in 1976 Name Its original genus name ''Onega'' comes from the Onega Peninsula of the White Sea, where the first fossils were found. The species name was given to honour V.A. Stepanov, who discovered the Ediacaran fossil site on the Letniy Bereg ("Summer Coast") in 1972, on the Onega Peninsula, the first Proterozoic site found in the Arkhangelsk Oblast. The original generic name is previously occupied by the hemipteran genus ''Onega'' Distant (1908). Ivantsov ''et al.'' (2019) coined a replacement generic name ''Cephalonega''. Morphology The small fossils, which range up to long, have oval outlines and low bodies with an articulated central zone built of isomers encircled by an undivided zone. The surface of the undivided region of ''Cephalonega'' is covered with small tubercles. ''Cephalonega'' was originally described b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proarticulata
Proarticulata is a proposed phylum of extinct, bilaterally symmetrical animals known from fossils found in the Ediacaran (Vendian) marine deposits, and dates to approximately . The name comes from the Greek () = "before" and Articulata, i.e. prior to animals with true segmentation such as annelids and arthropods. This phylum was established by Mikhail A. Fedonkin in 1985 for such animals as '' Dickinsonia'', ''Vendia'', '' Cephalonega'', '' Praecambridium'' and currently many other Proarticulata are described (see list). Due to their simplistic morphology, their affinities and mode of life are subject to debate. They are almost universally considered to be metazoans, and due to possessing a clear central axis have been suggested to be stem- bilaterians. In the traditional interpretation, the Proarticulatan body is divided into transverse articulation (division) into isomers as distinct from the transverse articulation segments in annelids and arthropods, as their individual is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vendomia
''Dickinsonia'' is an extinct genus of basal animal that lived during the late Ediacaran period in what is now Australia, China, Russia and Ukraine. The individual ''Dickinsonia'' typically resembles a bilaterally symmetrical ribbed oval. Its affinities are presently unknown; its mode of growth is consistent with a stem-group bilaterian affinity, though some have suggested that it belongs to the fungi, or even an "extinct kingdom". It lived during the late Ediacaran (part of Precambrian). The discovery of cholesterol molecules in fossils of ''Dickinsonia'' lends support to the idea that ''Dickinsonia'' was an animal. Description ''Dickinsonia'' fossils are known only in the form of imprints and casts in sandstone beds. The specimens found range from a few millimetres to about in length, and from a fraction of a millimetre to a few millimetres thick. They are nearly bilaterally symmetric, segmented, round or oval in outline, slightly expanded to one end (i.e. egg-shaped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dickinsonia
''Dickinsonia'' is an extinct genus of basal animal that lived during the late Ediacaran period in what is now Australia, China, Russia and Ukraine. The individual ''Dickinsonia'' typically resembles a bilaterally symmetrical ribbed oval. Its affinities are presently unknown; its mode of growth is consistent with a stem-group bilaterian affinity, though some have suggested that it belongs to the fungi, or even an "extinct kingdom". It lived during the late Ediacaran (part of Precambrian). The discovery of cholesterol molecules in fossils of ''Dickinsonia'' lends support to the idea that ''Dickinsonia'' was an animal. Description ''Dickinsonia'' fossils are known only in the form of imprints and casts in sandstone beds. The specimens found range from a few millimetres to about in length, and from a fraction of a millimetre to a few millimetres thick. They are nearly bilaterally symmetric, segmented, round or oval in outline, slightly expanded to one end (i.e. egg-shaped out ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran
The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and the beginning of the Phanerozoic Eon. It is named after the Ediacara Hills of South Australia. The Ediacaran Period's status as an official geological period was ratified in 2004 by the International Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years. Although the period takes its name from the Ediacara Hills where geologist Reg Sprigg first discovered fossils of the eponymous Ediacaran biota in 1946, the type section is located in the bed of the Enorama Creek within Brachina Gorge in the Flinders Ranges of South Australia, at . The Ediacaran marks the first appearance of widespread multicellular fauna following the end of Snowball Earth glaciation events, the so-called Ediacaran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yorgia
''Yorgia waggoneri'' is a discoid Ediacaran organism. It has a low, segmented body consisting of a short wide "head", no appendages, and a long body region, reaching a maximum length of . It is classified within the extinct animal phylum Proarticulata. Etymology The generic name ''Yorgia'' comes from the Yorga river on the Zimnii Bereg (Winter Coast) of the White Sea, where the first specimens were found. The specific name ''Yorgia waggoneri'' honors the American paleontologist Ben Waggoner, who found the first specimen. Morphology The body plan of the ''Yorgia'' and other proarticulates is unusual for solitary (non-colonial) metazoans. These bilateral organisms have segmented metameric bodies, but left and right transverse elements (isomers) are organized in an alternating pattern relatively to the axis of the body – they are not direct mirror images. This phenomenon is described as the symmetry of glide reflection, which is a characteristic also found in the similar ''Spri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeaspinus
''Archaeaspinus fedonkini'' is an extinct proarticulatan organism from the Late Precambrian (Ediacaran) period. Background ''Archaeaspinus'' was discovered in Zimnii Bereg, the Winter Coast of the White Sea in Russia, by A. Yu. Ivantsov in 2001. Since then, numerous additional fossils have been attributed to the genus, mostly from that same type locality, but a small number from Flinders Ranges in South Australia as well.Mikhail A. Fodonkin, James G. Gehling, Kathleen Grey, Guy M. Narbonne, Patricia Vickers-Rich''The Rise of Animals, Evolution and Diversification of the Kingdom Animalia'' Johns Hopkins University Press, Baltimore, 2007 Originally called '' Archaeaspis''—a name already preoccupied by a redlichiid trilobite—in 2001 by Ivantsov, it was later recombined under its current name in 2007 by the same author. The type species ''A. fedonkini'' is the only species known to the genus. It appears in the fossil record between 571-551Ma. Description Like other genera w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Summer Coast
The Summer Coast (''Letniy Bereg'', russian: Летний Берег) is a coastal area in Arkhangelsk Oblast in northwest Russia. It is located on the western side of the Dvina Bay in the White Sea, on the Onega Peninsula, between the Northern Dvina delta and Cape Ukhtnavolok, opposite to the Winter Coast. The names reflect the fact that the pomors of the Dvina Bay were fishing at Summer Coast and Winter Coast in the summer and in the winter, respectively. Administratively, the Summer coast is shared between Primorsky District and the city of Severodvinsk of Arkhangelsk Oblast. Between 1940 and 1958, the coast was part of Belomorsky District, with the center in the selo of Pertominsk. The villages of Nyonoksa, Syuzma, Krasnaya Gora, Pertominsk, Unsky, Yarenga, and Lopshenga are all located at the Summer Coast. The coast is crossed by the Una Bay, a gulf in the Dvina Bay, which is about long. The villages of Una and Luda are located at the inner coast of the Una Bay. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skania
''Skania'' is a Middle Cambrian fossil arthropod that is closely related to the Early Cambrian ''Primicaris'' from the Chengjiang Biota, China. It bears a superficial resemblance to the Ediacaran The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and th ... organism '' Parvancorina''. A single specimens of ''Skania'' are known from the Greater Phyllopod bed of the Burgess Shale where they comprise < 0.01% of the community. While previously enigmatic, it is now thought to be a marrellomorph. References External links *[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eoporpita
''Eoporpita'' is a disc or ellipse-shaped Ediacaran fossil with unsure taxonomy/classification. It is known from its type species, ''Eoporpita'' ''medusa'', the only species within the genus ''Eoporpita''. Classification debate/interpretations There are a few different interpretations of ''Eoporpita''’s taxonomy. The taxobox to the right describes ''Eoporpita'' as Mary Wade first did in 1972 as a Hydrozoa member and within the phylum Cnidaria. However, more recently, ''Eoporpita'' has been reinterpreted as either a benthic organism like a xenophyophore or the internal contents of ''Aspidella'', together forming a holdfast for a frond-like organism. More research on ''Eoporpita'' is needed. Morphology General morphology: ''Eoporpita'' is circular with radial symmetry. Its surface is smooth with some radial striae and a raised central dome. Annular shaped chambers surround the central dome, similar in look to ring-shaped ripples in a water body. Its average radius is from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeopascichnus
''Palaeopascichnus'' is an Ediacaran fossil comprising a series of lobes, first originating before the Gaskiers glaciation; it is plausibly a protozoan, but probably unrelated to the classical 'Ediacaran biota'. Once thought to represent a trace fossil, it is now recognized as a body fossil and corresponds to the skeleton of an agglutinating organism. See also * List of Ediacaran genera * Palaeopascichnid A "Palaeopascichnid" describes a multitude of elongate fossils made up of multiple sausage-shaped chambers. They appear only in Ediacaran sediments. Fossils of Palaeopascichnids consist of an occasionally branching series of globular or elongate c ... References Ediacaran life Incertae sedis Ediacaran Europe Geology of Ukraine {{Ediacaran-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaria
''Ediacaria'' is a fossil genus dating to the Ediacaran Period of the Neoproterozoic Era. Unlike most Ediacaran biota, which disappeared almost entirely from the fossil record at the end of the Period, ''Ediacaria'' fossils have been found dating from the Baikalian age (850–650 Ma) of the Upper Riphean to 501 million years ago, well into the Cambrian Period. ''Ediacaria'' consists of concentric rough circles, radial lines between the circles and a central dome, with a diameter from 1 to 70 cm. Systematics and taxonomy ''Ediacaria'' was named by Reg Sprigg in 1947, after the Ediacara Hills in South Australia. Two species are recognised: ''E. flindersi'', described by Sprigg from the Pound Quartzite in the Ediacara Hills, and ''E. booleyi'', described in 1995 from a Late Cambrian deposit at Booley Bay (County Wexford), Ireland. The species were named after the Flinders Ranges and Booley Bay, respectively. ''Ediacaria'' is possibly a synonym for ''Aspidella ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclomedusa
''Cyclomedusa'' is a circular fossil of the Ediacaran biota; it has a circular bump in the middle and as many as five circular growth ridges around it. Many specimens are small, but specimens in excess of 20 cm are known. The concentric disks are not necessarily circular, especially when adjacent individuals interfere with each other's growth. Many radial segment lines — somewhat pineapple-like — extend across the outer disks. A few specimens show what might be a stem extending from the center in some direction or other. ''Cyclomedusa'' is widely distributed in Ediacaran strata, with a number of species described. It has also been found in sediments dating to the Mayanian (~). ''Cyclomedusa'' was originally thought to be a jellyfish but some specimens seem to be distorted to accommodate adjacent specimens on the substrate, apparently indicating a benthic (bottom-dwelling) creature. The markings do not match the musculature pattern of modern jellyfish. The fossils have b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
