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Fram Formation
The Fram Formation is an Upper Devonian (Frasnian) sequence of rock strata on Ellesmere Island that came into prominence in 2006 with the discovery in its rocks of examples of the transitional fossil, ''Tiktaalik'', a sarcopterygian or lobe-finned fish showing many tetrapod characteristics. Fossils of ''Laccognathus embryi'', a porolepiform lobe-finned fish, and ''Qikiqtania'', a close relative of ''Tiktaalik'', were also found in the formation. The Fram Formation is a Middle to Upper Devonian clastic wedge forming an extensive continental facies consisting of sediments derived from deposits laid down in braided stream systems that formed some 375 million years ago,Fossil pollen suggest that these rocks lie within the early and middle Frasnian Stage of the Devonian. at a time when the North American craton ("Laurentia") was straddling the equator. Paleobiota Vertebrates See also * List of fossiliferous stratigraphic units in Nunavut * Escuminac Formation, another Frasnian-aged ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qikiqtania
''Qikiqtania'' (pronounced "kick-kiq-tani-ahh") is an extinct genus of elpistostegalian tetrapodomorph from the Late Devonian (early Frasnian stage) Fram Formation of Nunavut, Canada. The genus contains a single species, ''Q. wakei'', known from a partial skeleton. Analysis of the fin bones suggests that ''Qikiqtania'' was well-suited to swimming, and likely incapable of walking or supporting itself out of the water, as has been suggested for the closely related ''Tiktaalik''. Discovery and naming The holotype specimen of ''Qikiqtania'', NUFV 137, was discovered in 2004 in layers of the late Devonian (Frasnian)-dated Fram Formation of southern Ellesmere Island, Nunavut, Canada. The holotype specimen consists of lower jaws, partial left upper jaw and palate, gulars, ceratohyals, an articulated left pectoral fin and various articulated scales. The fossil remains of Qikiqtania were discovered east of the site where Tiktaalik was discovered, but from a slightly lower horizon in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palynology
Palynology is the "study of dust" (from grc-gre, παλύνω, palynō, "strew, sprinkle" and '' -logy'') or of "particles that are strewn". A classic palynologist analyses particulate samples collected from the air, from water, or from deposits including sediments of any age. The condition and identification of those particles, organic and inorganic, give the palynologist clues to the life, environment, and energetic conditions that produced them. The term is commonly used to refer to a subset of the discipline, which is defined as "the study of microscopic objects of macromolecular organic composition (i.e., compounds of carbon, hydrogen, nitrogen and oxygen), not capable of dissolution in hydrochloric or hydrofluoric acids". It is the science that studies contemporary and fossil palynomorphs (paleopalynology), including pollen, spores, orbicules, dinocysts, acritarchs, chitinozoans and scolecodonts, together with particulate organic matter (POM) and kerogen found in sedimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tristichopteridae
Tristichopterids (Tristichopteridae) were a diverse and successful group of tetrapodomorph fishes living throughout the Middle and Late Devonian. They first appeared in the Eifelian stage of the Middle Devonian. Within the group sizes ranged from a few tens of centimeters (''Tristichopterus'') to several meters (''Hyneria'' and ''Eusthenodon''). Some tristichopterids share some of the features of the elpistostegalians, a diverse clade of fishes close to the origin of (and including) tetrapods. This mainly concerns the shape of the skull and a reduction in size of the posterior fins. An old and persistent notion is that ''Eusthenopteron'' was able to crawl onto land using its fins. However, there is no evidence actually supporting this idea.M. Laurin, F. J. Meunier, D. Germain, and M. Lemoine 2007A microanatomical and histological study of the paired fin skeleton of the Devonian sarcopterygian ''Eusthenopteron foordi Journal of Paleontology'' 81: 143–153. All tristichopterids h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eusthenopteron
''Eusthenopteron'' (from el, εὖ , 'good', el, σθένος , 'strength', and el, πτερόν 'wing' or 'fin') is a genus of prehistoric sarcopterygian (often called lobe-finned fishes) which has attained an iconic status from its close relationships to tetrapods. Early depictions of this animal show it emerging onto land; however, paleontologists now widely agree that it was a strictly aquatic animal.M. Laurin, F. J. Meunier, D. Germain, and M. Lemoine 2007A microanatomical and histological study of the paired fin skeleton of the Devonian sarcopterygian ''Eusthenopteron foordi'' ''Journal of Paleontology'' 81: 143–153. The genus ''Eusthenopteron'' is known from several species that lived during the Late Devonian period, about 385 million years ago. ''Eusthenopteron'' was first described by J. F. Whiteaves in 1881, as part of a large collection of fishes from Miguasha, Quebec. Some 2,000 ''Eusthenopteron'' specimens have been collected from Miguasha, one of which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bothriolepis NT Small
''Bothriolepis'' (from el, βόθρος , 'trench' and el, λεπίς 'scale') was a widespread, abundant and diverse genus of antiarch placoderms that lived during the Middle to Late Devonian period of the Paleozoic Era. Historically, ''Bothriolepis'' resided in an array of paleo-environments spread across every paleocontinent, including near shore marine and freshwater settings. Most species of ''Bothriolepis'' were characterized as relatively small, benthic, freshwater detritivores (organisms that obtain nutrients by consuming decomposing plant/animal material), averaging around in length. However, the largest species, ''B. rex'', had an estimated bodylength of . Although expansive with over 60 species found worldwide, comparatively ''Bothriolepis'' is not unusually more diverse than most modern bottom dwelling species around today. Classification ''Bothriolepis'' is a genus placed within the placoderm order Antiarchi. The earliest antiarch placoderms first appeared ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Plate
A plate in animal anatomy may refer to several things: Flat bones (examples: bony plates, dermal plates) of vertebrates * an appendage of the Stegosauria group of dinosaurs * articulated armoured plates covering the head of thorax of Placodermi (literally "plate-skinned"), an extinct class of prehistoric fish (including skull, thoracic and tooth plates) * bony shields of the Ostracoderms (armored jawless fishes) such as the dermal head armour of members of the class Pteraspidomorphi that include dorsal, ventral, rostral and pineal plates * plates of a carapace, such as the dermal plates of the shell of a turtle * dermal plates partly or completely covering the body of the fish in the order Gasterosteiformes that includes the sticklebacks and relatives * plates of dermal bones of the armadillo * Zygomatic plate, a bony plate derived from the flattened front part of the zygomatic arch (cheekbone) in rodent anatomy Other flat structures * hairy plate-like keratin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bothriolepis
''Bothriolepis'' (from el, βόθρος , 'trench' and el, λεπίς 'scale') was a widespread, abundant and diverse genus of antiarch placoderms that lived during the Middle Devonian, Middle to Late Devonian period of the Paleozoic Era. Historically, ''Bothriolepis'' resided in an array of paleo-environments spread across every paleocontinent, including near shore marine and freshwater settings. Most species of ''Bothriolepis'' were characterized as relatively small, benthic, freshwater detritivores (organisms that obtain nutrients by consuming decomposing plant/animal material), averaging around in length. However, the largest species, ''B. rex'', had an estimated bodylength of . Although expansive with over 60 species found worldwide, comparatively ''Bothriolepis'' is not unusually more diverse than most modern bottom dwelling species around today. Classification ''Bothriolepis'' is a genus placed within the placoderm order Antiarchi. The earliest antiarch placoderms fir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bothriolepididae
Bothriolepididae is a family of antiarch placoderms, known from the Emsian, to Famennian. Taxonomy The cladogram is fromBothriolepid antiarchs (Vertebrata, Placodermi) from the Devonian of the north-western part of the East European Platform. {{Clade, style={{Clade , label1= Bothriolepidoidei , 1={{Clade , 1={{Clade , 1='' Microbrachius'' , 2='' Wudinolepis'' , 2={{Clade , 1={{Clade , 1=''Dianolepis'' , 2=''Jiangxilepis'' , 3='' Kirgisolepis'' , 4='' Tenizolepis'' , 2={{Clade , 1=''Monarolepis'' , 2={{Clade , 1=''Bothriolepis'' , 2=''Grossilepis Antiarchi ("opposite anus") is an order of heavily armored placoderms. The antiarchs form the second-most successful group of placoderms after the arthrodires in terms of numbers of species and range of environments. The order's name was coi ...'' , 3='' Vietnamaspis'' References {{Refl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterolepis (fish)
''Asterolepis'' is an extinct genus of antiarch placoderms from the Devonian of North and South America and Europe. They were heavily armored flat-headed benthic detritivores with distinctive jointed limb-like pectoral fins and hollow spine. The armor plate gives the ''Asterolepis'' a box-like shape. Its pectoral fins are also armored but the caudal and dorsal fin are not. The first fossils were named by M. Eichwald in 1840 after noticing star-like markings on the fossils. Etymology "Aster-" means star while "-lepis" means scales. Confusion surrounded the first fossils discovered of this genus, as naturalists were unable to ascertain their place among fishes and they were first named Chelonichthys. Later very fine specimens were found in the Old Red Sandstone of Russia and Professor Asmus of Dorpat sent them to the British Museum, noticing fossils exhibited star-like markings. That is when the name Chelonichthys was abandoned for ''Asterolepis'' which Eichwald proposed. Des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placodermi
Placodermi (from Greek πλάξ 'plate' and δέρμα 'skin', literally 'Plate (animal anatomy), plate-skinned') is a Class (biology), class of armoured prehistoric fish, known from fossils, which lived from the Silurian to the end of the Devonian period. Their head and thorax were covered by articulated armoured plates and the rest of the body was scale (zoology), scaled or naked, depending on the species. Placoderms were among the first jawed fish; their Fish jaw, jaws likely evolved from the first of their gill arches. Placoderms are thought to be paraphyly, paraphyletic, consisting of several distinct Outgroup (cladistics), outgroups or sister taxon, sister taxa to all living jawed vertebrates, which originated among their ranks. In contrast, one 2016 analysis concluded that placodermi are likely monophyletic, though these analyses have been further dismissed with more transitional taxa between placoderms and modern gnathosthomes, solidifying their paraphyletic status. Plac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vendom Fiord
Vendom Fiord is a natural inlet in the south-west of Ellesmere Island, Nunavut in the Arctic Archipelago. To the south, it opens into Baumann Fiord Baumann Fiord is a natural inlet in the south-west of Ellesmere Island, Qikiqtaaluk Region, Nunavut in the Arctic Archipelago. To the west, it opens into Norwegian Bay. Hoved Island Hoved Island is part of the Qikiqtaaluk Region of the Can .... References Ellesmere Island Fjords of Qikiqtaaluk Region {{canada-fjord-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterolepidoidei
Antiarchi ("opposite anus") is an order of heavily armored placoderms. The antiarchs form the second-most successful group of placoderms after the arthrodires in terms of numbers of species and range of environments. The order's name was coined by Edward Drinker Cope, who, when examining some fossils that he thought were armored tunicates related to '' Chelysoma'', mistakenly thought that the orbital fenestra (i.e., the hole in the headshield for the eyes, nose and pineal foramen) was the opening for the mouth, or oral siphon, and that the opening for the anal siphon was on the other side of the body, as opposed to having both oral and anal siphons together at one end. The front portions of their bodies were heavily armored, to the point of literally resembling a box with eyes, with the sometimes scaled, sometimes naked rear portions often becoming sinuous, particularly with later forms. The pair of pectoral fins were modified into a pair of caliper-like, or arthropod-l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
