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Petalichthyida
Petalichthyida is an extinct order of small, flattened placoderm fish. They are typified by their splayed pectoral fins, exaggerated lateral spines, flattened bodies, and numerous tubercles that decorated all of the plates and scales of their armor. They reached a peak in diversity during the Early Devonian and were found throughout the world, particularly in Europe (especially in Germany), North America, Asia, South America, and Australia. The petalichthids '' Lunaspis'' and '' Wijdeaspis'' are among the best known. The earliest and most primitive known petalichthyid is '' Diandongpetalichthys'', which is from earliest Devonian-aged strata of Yunnan. The presence of ''Diandongpetalichthys'', along with other primitive petalichthyids including '' Neopetalichthys'' and '' Quasipetalichthys'', and more advanced petalichthyids, suggest that the order may have arisen in China, possibly during the late Silurian. Because they had compressed body forms, it is speculated they wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petalichthyida
Petalichthyida is an extinct order of small, flattened placoderm fish. They are typified by their splayed pectoral fins, exaggerated lateral spines, flattened bodies, and numerous tubercles that decorated all of the plates and scales of their armor. They reached a peak in diversity during the Early Devonian and were found throughout the world, particularly in Europe (especially in Germany), North America, Asia, South America, and Australia. The petalichthids '' Lunaspis'' and '' Wijdeaspis'' are among the best known. The earliest and most primitive known petalichthyid is '' Diandongpetalichthys'', which is from earliest Devonian-aged strata of Yunnan. The presence of ''Diandongpetalichthys'', along with other primitive petalichthyids including '' Neopetalichthys'' and '' Quasipetalichthys'', and more advanced petalichthyids, suggest that the order may have arisen in China, possibly during the late Silurian. Because they had compressed body forms, it is speculated they wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunaspis
''Lunaspis'' is an extinct genus of armor-plated petalichthyid placoderm fish that lived in shallow marine environments of the Early Devonian period, from approximately 409.1 to 402.5 million year ago.Fossilworks: Gateway to the Paleobiology database. Retrieved March 6, 2017, from Fossilworks, http://www.fossilworks.org/cgi-bin/bridge.pl?page=paleodb Fossils have been found in Germany, China and Australia. There are three different identified species of within the genus ''Lunaspis'': ''L. broilii, L. heroldi, and L. prumiensis.'' Like many other petalichthyid fish, ''Lunaspis'' are flat and have elongated pectoral spines, shortened thoracic armor, and dorsally oriented eyes. ''Lunaspis'' has been studied mainly by German, Australian, and Chinese palaeontologists because of where it is most commonly encountered. The tails are long and thin and resemble a whip, somewhat like extant skates and rays. Description A typical individual of ''Lunaspis'' was a flattened fish wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diandongpetalichthys
''Diandongpetalichthys liaojiaoshanensis'' is an extinct petalichthid placoderm from the Early Devonian of China. Fossils Several specimens, in the forms of one complete and several incomplete skull roofs, disarticulated portions of the trunk shield, and spines, are known, found in the Devonian aged Liaojiaoshan Hill of Qujing, Yunnan, a non-marine portion of the Xishancun Formation, in the Cuifengshan Group. Phylogeny The holotype of ''D. liaojiaoshanensis'' is a poorly preserved, incomplete skull roof, and was, at the time of its description in 1978, regarded as "Petalichthyida ''incertae sedis''. In light of more, better preserved specimens that show features in common with primitive arthrodires Arthrodira (Greek for "jointed neck") is an order of extinct armored, jawed fishes of the class Placodermi that flourished in the Devonian period before their sudden extinction, surviving for about 50 million years and penetrating most marine ec ..., such as actinolepids and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neopetalichthys
''Neopetalichthys yenmenpaensis'' is an extinct petalichthid placoderm from the Early Devonian of China. Fossils The holotype and only known specimen is a poorly preserved partial, and elongated skull from Emsian-aged strata in Sichuan. The skull may be around in length. Phylogeny Denison 1978 questions ''Neopetalichthys''' placement within Petalichthyida, regarding it as Placodermi ''incertae sedis'', though he does acknowledge that the skull has anatomical features in common with petalichthyids.). According to Zhu's 1991 redescription of ''Diandongpetalichthys ''Diandongpetalichthys liaojiaoshanensis'' is an extinct petalichthid placoderm from the Early Devonian of China. Fossils Several specimens, in the forms of one complete and several incomplete skull roofs, disarticulated portions of the trunk s ...'',Zhu, M. "New information on ''Diandongpetalichthys'' (Placodermi: Petalichthyida)." Early vertebrates and related problems of evolutionary biology. Science Press, Be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasipetalichthys
''Quasipetalichthys haikouensis'' is the type and only known species of the extinct petalichthid placoderm, ''Quasipetalichthys''. Fossil remains of ''Quasipetalichthys'' have been found in the Middle Devonian, Givetian faunal stage of China. Fossils ''Quasipetalichthys'' is known primarily from two poorly preserved skulls from the Givetian-aged Haikou Formation of Haikou, Kunming, China, where they were found in association with remains of antiarch placoderms such as ''Bothriolepis sinensis'', and '' Hunanolepis''. The larger of the two skulls may have been around in length. Phylogeny ''Q. haikouensis'' is considered a basal petalichthyid (though in 1978 Denison referred to it as being "aberrant"). In Zhu's 1991 redescription of ''Diandongpetalichthys'',Zhu, M. "New information on ''Diandongpetalichthys'' (Placodermi: Petalichthyida)." Early vertebrates and related problems of evolutionary biology. Science Press, Beijing (1991): 179-192. ''Quasipetalichthys'' was place ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurycaraspis
''Eurycaraspis incilis'' is an extinct petalichthid placoderm from the Middle Devonian of China. It is closely related to ''Quasipetalichthys ''Quasipetalichthys haikouensis'' is the type and only known species of the extinct petalichthid placoderm, ''Quasipetalichthys''. Fossil remains of ''Quasipetalichthys'' have been found in the Middle Devonian, Givetian faunal stage of China ...''. Anatomy ''Eurycaraspis incilis'' differs from ''Quasipetalichthys'' by having a more circular-shaped skull. Phylogeny ''Eurycaraspis incilis'' is considered a basal petalichthyid, and is placed in Quasipetalichthyidae as ''Quasipetalichthys sister taxon. Quasipetalichthyidae, in turn, is considered the sister group of Macropetalichthyidae. References Fossil taxa described in 1991 Placoderms of Asia Petalichthyida Placoderm genera {{Placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macropetalichthys
''Macropetalichthys'' is a genus of placoderm fish, named by Norwood and Owen in 1846; the name "''Macropetalichthys''" means "armour-plated fish". It was assigned to Arthrodira by Woodward (1891); and to Petalichthida by Sepkoski (2002). It contains a single species, ''M. rapheidolabis''. * Range: Early Devonian of Europe, China & Australia * Characters: Like primitive Arthrodira. Dorsoventrally compressed; orbits face dorsally; widely splayed pectoral fins, with cornua common; no post-pectoral plates; plates ornamented with linear rows of tubercles; strictly benthonic? References Monotypic fish genera Placoderm genera Placoderms of Asia Placoderms of Australia Placoderms of Europe Petalichthyida {{Placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasipetalichthyidae
Quasipetalichthyidae is a family of primitive petalichthyid placoderms from Givetian-aged marine strata of Yunnan, China, and possibly Vietnam. The family contains two confirmed genera, ''Quasipetalichthys'', and ''Eurycaraspis'', which differ from the more advanced macropetalichthyids by having more squared skulls that have the eye sockets placed on the side of their skulls, rather than nearer to the center. More basal petalichthyids, such as ''Diandongpetalichthys'' and ''Neopetalichthys ''Neopetalichthys yenmenpaensis'' is an extinct petalichthid placoderm from the Early Devonian of China. Fossils The holotype and only known specimen is a poorly preserved partial, and elongated skull from Emsian-aged strata in Sichuan. The sk ...'', differ from the quasipetalichthyids by having comparatively elongated skulls. References Placoderms of Asia Placoderm families Petalichthyida Middle Devonian extinctions Middle Devonian first appearances {{Placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emsian
The Emsian is one of three faunal stages in the Early Devonian Epoch. It lasted from 407.6 ± 2.6 million years ago to 393.3 ± 1.2 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 agoniatitid 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 Goniatitida rises in the end of Zlichovian stage (Siberian representation; corresponds to early Eifelian and after the end of Early Devonian, before 391.9 mya). Later agoniatitid ammonoids would die out in the Taghanic event in the upper middle Givetian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
