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Rangeomorph
The rangeomorphs are a group of Ediacaran Ediacaran biota, fossils. Ediacarans are the oldest large fossil organisms on earth, and many are not self-evidently related to anything else that has ever lived. However, some Ediacarans clearly resemble each other. Palentologists have not been able to agree on what else, if anything, is related to these organisms, so Ediacarans are usually classified into groups based on their appearance. These "Form taxon, form taxa" allow scientists to study and discuss Ediacarans when they cannot know what kind of living things they were, or how they were genetically related to each other. Rangeomorphs look roughly like fern fronds or feathers arranged around a central axis; the group is defined as Ediacarans with a similar appearance and structure to the genus ''Rangea''. Some researchers, such as Pflug and Narbonne, believe all rangeomorphs were more closely related to each other than to anything else. If true, this would make the group a natural tax ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hylaecullulus
''Hylaecullulus fordi'', also described as dumbbells, is an extinct species of Ediacaran Petalonamae, petalonamid whose fossils were found in the Charnwood Forest of Leicestershire, England. It serves as an important rangeomorph because of its multifoliate anatomy. Its overall body plan is similar to that of a goblet, from which its name, ''Hylaecullulus'', alongside its common name of dumbbell, is derived from. Etymology The name ''Hylaecullulus fordi'' is derived from the Ancient Greek words , which means 'from the woods' (in reference to its occurrence within Charnwood Forest), and , which means "small goblet". The name of the type species, "fordi", was given to honour Trevor D. Ford, Trevor Ford, who made important contributions to the List of Ediacaran genera, Ediacaran fauna. Discovery ''Hylaecullulus fordi'' was discovered in the hilly tract of Charnwood Forest in 2018 by a team led by C. G. Kenchington. This team found six well-preserved fossils at the top of the Bradg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hapsidophyllas
''Hapsidophyllas'' is a rare Ediacaran rangeomorph fossil found at Mistaken Point, Newfoundland, Canada. It was first identified by Emily Bamforth and Guy Narbonne in 2009. Because its characteristic flexible leaflet structure is dissimilar to other known rangeomorphs, Bamforth and Narbonne describe it as a new rangeomorph form, called hapsidophyllid. The only other known hapsidophyllid is the Ediacaran frond '' Frondophyllas grandis'', which shares the network-like configuration of leaflets seen in ''Hapsidophyllas''. Currently, the ''Hapsidophyllas flexibilis'' holotype resides in its type locality in the Mistaken Point Ecological Reserve, and a cast of the specimen is on display at the Royal Ontario Museum in Toronto, Canada. Etymology The generic name roughly translates to 'A network of leaves', from the Greek words ''hapsis'', to mean 'network' or 'mesh', and ''phyllon'', to mean 'leaves'. Description The ''Hapsidophyllas flexibilis'' holotype is 110 mm long and 4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avalofractus
''Avalofractus abaculus'' is a frond-like rangeomorph fossil described from the Ediacaran of the Trepassey Formation, Spaniard's Bay, Newfoundland. Morphology ''Avalofractus'' displays a strongly fractal body shape, with four levels of nearly perfectly self-similar, pinnate, alternate branches. It was about 5 cm long on average, with a 1 cm-diameter holdfast at the base of the frond. The stem length is from 1/3 to 1/2 that of the whole frond. It is quite similar to '' Rangea'', even if with distinct morphological differences that justify the creation of a new genus (e.g. absence of subsidiary quilts, frond elements free to rotate independently instead of being attached to each other by a membrane). A 2017 analysis of ''Avalofractus'' fossils found that the growth of the animal and its morphology was dependent on the amount of nutrient, suggesting that the phenotype of Ediacaran organisms was flexible in response to environmental conditions. Distribution In contrast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frondophyllas
''Frondophyllas'' is an extinct, monotypic animal genus in the clade ''Rangeomorpha''. It was found at the Mistaken Point on the Avalon Peninsula in Newfoundland, Canada in 2008 by Bamforth and Anderson. The single species is ''Frondophyllas grandis'' and only two specimens have been discovered. Both specimens are incomplete, but one extends to one meter long, making it one of the largest Ediacaran macrofossils. The species name: ''grandis'', comes from its size, and the genus name: ''Frondophyllas'' means "frond with leaves". The organism has a base structure with numerous fronds attached to it. It is the only Ediacaran organism to have distinct leaflets. Evidence suggests that ''F. grandis'' may have been tethered to the seafloor and used these leaflets to "filter feed", or live off nutrients provided by a current. One of the reasons fossils of this species are so rare is because it was a soft-bodied organism. It is believed that ''F. grandis'' was preserved because it was ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charnia
''Charnia'' is an extinct genus of frond-like lifeforms belonging to the Ediacaran biota with segmented, leaf-like ridges branching alternately to the right and left from a zig-zag medial suture (thus exhibiting glide reflection, or opposite isometry). The genus ''Charnia'' was named after Charnwood Forest in Leicestershire, England, where the first fossilised specimen was found; the species was named after Roger Mason, a schoolboy who was believed to have initially discovered it. ''Charnia'' is significant because it was the first Precambrian fossil to be recognized as such. The living organism grew on the sea floor, 570 to 550 million years ago, and is believed to have fed on nutrients in the water. Despite ''Charnia'' fern-like appearance, it is not a photosynthetic plant or alga because the nature of the fossil beds where specimens have been found implies that it originally lived in deep water, well below the photic zone where photosynthesis can occur. Diversity Severa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trepassia
''Trepassia'' is a 579 million-year-old fossil of Ediacaran rangeomorph. It was first discovered by Guy M. Narbonne, a professor at Queen's University in Ontario, Canada and colleagues in 2009. Three years later, Martin D. Brasier added additional description to ''Trepassia.'' The generic name is taken from the French word, trépassés, which translates to "those that have departed forever" (or "corpses") and honors the Trepassey community in Newfoundland. It was originally described as ''Charnia wardi''; it was referred under this synonym in a 2016 paper. Morphology ''Trepassia'' is one of the oldest known rangeomorphs and spanned over one meter in length. Longest specimens of ''T. wardae'' reached .M. LAFLAMME, G. M. NARBONNE, C. GREENTREE & M. M. ANDERSON. 2016. Morphology and taphonomy of an Ediacaran frond: Charnia from the Avalon Peninsula of Newfoundland. Department of Geological Sciences and Geological Engineering, Queen’s University, Kingston, Ontario, Canada K7L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Culmofrons
''Beothukis'' is a rare fossil frond-like member of the Rangeomorpha, described from the Ediacaran of Mistaken Point, Newfoundland. It had been identified since 1992, referred in papers as a "spatulate frond" or "flat recliner", but not formally described until 2009. The original fossils from which the genus has been described are still ''in situ'', but replicas are preserved at the Memorial University of Newfoundland and at the Oxford University Museum of Natural History. Claims of a stem have been contentious, and based largely on structures that have subsequently been determined to be erosional scours, and is so considered to be a recliner Morphology ''Beothukis'' appears as a frond composed of two asymmetrical rows of branches that depart from a central growth axis, 12.5–15.5 cm long and 4.5–6 cm wide. Secondary growth is present around the tip. Secondary order units cross the primary order axes as is common in the Charnida The alternations are irregularly sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beothukis
''Beothukis'' is a rare fossil frond-like member of the rangeomorph, Rangeomorpha, described from the Ediacaran of Mistaken Point, Newfoundland (island), Newfoundland. It had been identified since 1992, referred in papers as a "spatulate frond" or "flat recliner", but not formally described until 2009. The original fossils from which the genus has been described are still ''in situ'', but replicas are preserved at the Memorial University of Newfoundland and at the Oxford University Museum of Natural History. Claims of a stem have been contentious, and based largely on structures that have subsequently been determined to be erosional scours, and is so considered to be a recliner Morphology ''Beothukis'' appears as a frond composed of two asymmetrical rows of branches that depart from a central growth axis, 12.5–15.5 cm long and 4.5–6 cm wide. Secondary growth is present around the tip. Secondary order units cross the primary order axes as is common in the Charnida T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran Biota
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 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 term "Ediacara biota" has received criticism from some scientists due to its alleged inconsistency, arbitrary exclusion of certain fossils, and inability to be precisely defined. 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 Ediacara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charniidae
Charniidae is a family of rangeomorphs. It is the only non-monotypic family of Rangeomorpha. Distribution From the Ediacaran of Australia, Canada, Russia and the United Kingdom, to the Cambrian of Canada. Taxonomy The family presents 6 genera: * †''Beothukis'' * †'' Bomakellia'' * †'' Bradgatia'' * †''Charnia'' * †''Culmofrons ''Beothukis'' is a rare fossil frond-like member of the Rangeomorpha, described from the Ediacaran of Mistaken Point, Newfoundland. It had been identified since 1992, referred in papers as a "spatulate frond" or "flat recliner", but not formall ...'' * †'' Paracharnia'' Gallery Bomakellia_kelleri.JPG , Artists interpretation of the enigmatic '' Bomakellia kelleri''. Charnia.png , Fossil specimen of '' Charnia masoni''. Paracharnia_dengyingensis.png , Artists interpretation of '' Paracharnia dengyingensis''. See also *'' Rangea'' References Rangeomorpha Charniidae Ediacaran life {{Ediacaran-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pectinifrons
''Pectinifrons'' was a rangeomorph, a member of the Ediacara biota found at Mistaken Point, Newfoundland. It was a multi-branched organism with a comb-like appearance. It grew by adding fronds, then inflating them. See also * List of Ediacaran genera The existence of life, especially that of animals, before the Cambrian had long been the subject of debate in paleontology. The apparent suddenness of the Cambrian explosion had no firm explanation, and Charles Darwin himself recognized the chal ... References Rangeomorpha Ediacaran North America {{Ediacaran-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rangeidae
''Rangea'' is a frond-like Ediacaran fossil with six-fold radial symmetry. It is the type genus of the rangeomorphs. ''Rangea'' was the first complex Precambrian macrofossil named and described anywhere in the world. ''Rangea'' was a centimetre- to decimetre-scale frond characterised by a repetitive pattern of self-similar branches and a sessile benthic lifestyle. Fossils are typically preserved as moulds and casts exposing only a leafy petalodium, and the rarity and incompleteness of specimens has made it difficult to reconstruct the three-dimensional (3D) morphology of the entire organism.Sharp, Alana C., Alistair R. Evans, Siobhan A. Wilson, and Patricia Vickers-Rich. "First Non-destructive Internal Imaging of Rangea, an Icon of Complex Ediacaran Life." Precambrian Research 299 (2017): 303-08. doi: 10.1016/j.precamres.2017.07.023 Fossilized ''Rangea'' consists of several vanes. Each vane has a foliate shape with a series of recessed furrows that run outwards at varying angle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
