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Wigwamiella
'' Pseudorhizostomites howchini'' is a enigmatic member of the Ediacaran Biota which was originally been thought to have been a jellyfish of some kind (Sepkoski, 2002). ''P. howchini'' is now though to either have been a pseudofossil, a gas escape structure or perhaps the result of a rangeomorph holdfast being pulled by currents or, if any of these possibilities are not true, some other force from the sediments which enclosed the fossil. Distribution and discovery Reginald Sprigg found the Holotype of ''P. howchini'' within the Flinders Ranges of South Australia. Fossils of ''Pseudorhizostomites'' also occur within the White Sea region of Russia on Zimnii Bereg, the Dniester River Basin of Podolia, Ukraine and Gornaya Baskkiria of the Ryauzyak Basin. These fossils are commonly found at all locations. Classification and interpretations Originally, Sepkoski (2002) suggested the possibility of the problematic fossils as being a Jellyfish. Although a more modern and updated int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wigwamiella
'' Pseudorhizostomites howchini'' is a enigmatic member of the Ediacaran Biota which was originally been thought to have been a jellyfish of some kind (Sepkoski, 2002). ''P. howchini'' is now though to either have been a pseudofossil, a gas escape structure or perhaps the result of a rangeomorph holdfast being pulled by currents or, if any of these possibilities are not true, some other force from the sediments which enclosed the fossil. Distribution and discovery Reginald Sprigg found the Holotype of ''P. howchini'' within the Flinders Ranges of South Australia. Fossils of ''Pseudorhizostomites'' also occur within the White Sea region of Russia on Zimnii Bereg, the Dniester River Basin of Podolia, Ukraine and Gornaya Baskkiria of the Ryauzyak Basin. These fossils are commonly found at all locations. Classification and interpretations Originally, Sepkoski (2002) suggested the possibility of the problematic fossils as being a Jellyfish. Although a more modern and updated int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspidella
:Aspidella'' is also a homonym for the mushroom genus ''Saproamanita. ''Aspidella'' is an Ediacaran disk-shaped fossil of uncertain affinity. It is known from the single species ''A. terranovica''. Morphology ''Aspidella'' consists of disk-shaped fossils, with concentric rings and/or centripetal rays. The diameter of circular ''Aspidella'' varies from 1 to 180 mm.Peterson. P. 131 Most individuals are between 4 and 10 mm, but smaller individuals would presumably have decayed before they could fossilize. Other ''Aspidella'' take the form of ellipses, 3–8 cm long and 1–4 cm wide. Most have a central pimple. The rim of all specimens is made up by ridge-edged rays and/or concentric rings. Ecology The rarity of large individuals probably indicates that ''Aspidella'' were r-strategists, producing numerous offspring of which most died young. It is most common in deep-water sediments, but is a constituent of most Ediacaran fossil assemblages, including tho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Ediacaran Genera ...
This is a list of all described Ediacaran genera, including the Ediacaran biota. It contains 227 genera. References {{reflist, 30em * 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animalia
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aquatic Animals
An aquatic animal is any animal, whether invertebrate or vertebrate, that lives in water for most or all of its lifetime. Many insects such as mosquitoes, mayflies, dragonflies and caddisflies have aquatic larvae, with winged adults. Aquatic animals may breathe air or extract oxygen from water through specialised organs called gills, or directly through the skin. Natural environments and the animals that live in them can be categorized as aquatic (water) or terrestrial (land). This designation is polyphyletic. Description The term aquatic can be applied to animals that live in either fresh water or salt water. However, the adjective marine is most commonly used for animals that live in saltwater, i.e. in oceans, seas, etc. Aquatic animals (especially freshwater animals) are often of special concern to conservationists because of the fragility of their environments. Aquatic animals are subject to pressure from overfishing, destructive fishing, marine pollution, hunting, and clim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran Life
The Ediacaran (; formerly Vendian) biota is a taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (). These were composed of enigmatic tubular and frond-shaped, mostly sessile, organisms. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms. The Ediacaran biota may have undergone evolutionary radiation in a proposed event called the Avalon explosion, . This was after the Earth had thawed from the Cryogenian period's extensive glaciation. This biota largely disappeared with the rapid increase in biodiversity known as the Cambrian explosion. Most of the currently existing body plans of animals first appeared in the fossil record of the Cambrian rather than the Ediacaran. For macroorganisms, the Cambrian biota appears to have almost completely replaced the organisms that dominated the Ediacaran fossil record, although relationships are ... [...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 biota, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campanularia
''Campanularia'' is a genus of hydrozoans, in the family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ... Campanulariidae. Species *'' Campanularia abyssa'' Fraser, 1940 *'' Campanularia africana'' Stechow, 1923 *'' Campanularia agas'' Cornelius, 1982 *'' Campanularia ambiplica'' Mulder & Trebilcock, 1914 *'' Campanularia antarctica'' Ritchie, 1913 *'' Campanularia brevicaulis'' Nutting, 1915 *'' Campanularia breviscyphia'' Sars, 1857 *'' Campanularia certidens'' Fraser, 1947 *'' Campanularia compressima'' Kubota & Yamada, 1992 *'' Campanularia costata'' (Gravier-Bonnet, 1979) *'' Campanularia crenata'' Allman, 1876 *'' Campanularia denticulata'' Clark, 1877 *'' Campanularia diverticulata'' (Totton, 1930) *'' Campanularia erythraea'' (Stechow, 1923) *'' Campanularia fusiformis' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrozoan
Hydrozoa (hydrozoans; ) are a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water. The colonies of the colonial species can be large, and in some cases the specialized individual animals cannot survive outside the colony. A few genera within this class live in freshwater habitats. Hydrozoans are related to jellyfish and corals and belong to the phylum Cnidaria. Some examples of hydrozoans are the freshwater jelly (''Craspedacusta sowerbyi''), freshwater polyps ('' Hydra''), ''Obelia'', Portuguese man o' war (''Physalia physalis''), chondrophores (Porpitidae), "air fern" (''Sertularia argentea''), and pink-hearted hydroids (''Tubularia''). Anatomy Most hydrozoan species include both a polypoid and a medusoid stage in their lifecycles, although a number of them have only one or the other. For example, ''Hydra'' has no medusoid stage, while '' Liriope'' lacks the polypoid stage. Polyps The hydroid fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rugoconites Tenuirugosus
''Rugoconites'' is a genus of Ediacaran biota found as fossils in the form of a circular or oval-like impression preserved in high relief, six or more centimeters in diameter. The fossils are surrounded by frills that have been interpreted ( Wade 1972) as sets of tentacles. The bifurcating radial ribs, spreading from a central dome, serve to distinguish this genus from the sponge ''Palaeophragmodictya'', and may represent the channels of the gastrovascular system. Fossils of ''Rugoconites'' have been interpreted as early sponges, although this is countered by Sepkoski ''et al.'' (2002), who interpreted the organism as a free-swimming jellyfish-like cnidarian; similar to '' Ovatoscutum''. However, the fossil is consistently preserved as a neat circular form and its general morphology does not vary, therefore a benthic and perhaps slow-moving or sessile lifestyle is more likely. Ivantstov & Fedonkin (2002), suggest that ''Rugoconites'' may possess tri-radial symmetry and be a memb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petalonamid
The petalonamids (Petalonamae) are an extinct group of archaic animals typical of the Ediacaran biota, also called frondomorphs, dating from approximately 635 million years ago to 516 million years ago. They are benthic and motionless animals, that have the shape of leaves, fronds (frondomorphic), feathers or spindles and were initially considered algae, octocorals or sea pens. It is now believed that there are no living descendants of the group, which shares a probable relation to the Ediacaran animals known as Vendozoans. It is considered that the organisms were fluffy at least in appearance, as if "inflatable." They are particularly difficult to classify phylogenetically. Lacking mouths, intestines, reproductive organs, and with no preserved evidence of internal structures, these organisms' existence is very strange by current standards. The most widely accepted hypothesis is that they could suck nutrients from the water around them by osmosis. The fronds were composed of br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jellyfish
Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella-shaped bells and trailing tentacles, although a few are anchored to the seabed by stalks rather than being mobile. The bell can pulsate to provide propulsion for highly efficient animal locomotion, locomotion. The tentacles are armed with Cnidocyte, stinging cells and may be used to capture prey and defend against predators. Jellyfish have a complex Biological life cycle, life cycle; the medusa is normally the sexual phase, which produces planula larvae that disperse widely and enter a sedentary polyp (zoology), polyp phase before reaching sexual maturity. Jellyfish are found all over the world, from surface waters to the deep sea. Scyphozoans (the "true jellyfish") are exclusively marine habitats, marine, but some hydrozoans with a simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
