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Ateleaspididae
Ateleaspididae is a prehistoric jawless fish family in the class Osteostraci The class Osteostraci (meaning "bony shells") is an extinct taxon of bony-armored jawless fish, termed "ostracoderms", that lived in what is now North America, Europe and Russia from the Middle Silurian to Late Devonian. Anatomically speaking, ....Sansom, R. S. (2009). "Phylogeny, classification and character polarity of the Osteostraci (Vertebrata)". Journal of Systematic Palaeontology 7: 95–11. References External links Osteostraci Prehistoric jawless fish families {{Paleo-jawless-fish-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteostraci
The class Osteostraci (meaning "bony shells") is an extinct taxon of bony-armored jawless fish, termed "ostracoderms", that lived in what is now North America, Europe and Russia from the Middle Silurian to Late Devonian. Anatomically speaking, the osteostracans, especially the Devonian species, were among the most advanced of all known agnathans. This is due to the development of paired fins, and their complicated cranial anatomy. The osteostracans were more similar to lampreys than to jawed vertebrates in possessing two pairs of semicircular canals in the inner ear, as opposed to the three pairs found in the inner ears of jawed vertebrates. They are thought to be the sister-group to pituriaspids, and together, these two taxa of jawless vertebrates are the sister-group of gnathostomes. Several synapomorphies support this hypothesis, such as the presence of: sclerotic ossicles, paired pectoral fins, a dermal skeleton with three layers (a basal layer of isopedin, a middle layer of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ramsay Traquair
Ramsay Heatley Traquair Fellow of the Royal Society of Edinburgh, FRSE Fellow of the Royal Society of London, FRS (30 July 1840 – 22 November 1912) was a Scottish naturalist and palaeontologist who became a leading expert on fossil fish. Traquair trained as a medical doctor, but his thesis was on aspects of fish anatomy. He held posts as Professor of Natural History and Professor of Zoology in England and Ireland, before returning to his native Edinburgh to take up a post at the Royal Scottish Museum, Museum of Science and Art. He spent the rest of his career there, building up a renowned collection of fossil fish over a period of more than three decades. He published extensively on palaeoichthyology, authoring many papers and a series of monographs. His studies of rocks and fossils in Scotland overturned earlier work on fossil fish, establishing new taxonomic classifications. His honours included fellowships from a range of learned societies, including the Royal Society of E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ateleaspis
''Ateleaspis'' is an extinct genus of primitive ostracoderm fish that lived in the Early Silurian to Early Devonian periods. Like other ostracoderms, ''Ateleaspis'' had a head shield similar to that of ''Cephalaspis''. Species from Silurian period were found in Norway and Scotland, but now has been found also in Siberia Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of ... from Early Devonian period. Description ''Ateleaspis'' possibly is the most basal vertebrate with paired fins. ''Ateleaspis'' was a small fish (about 15 – 20 cm) and had a flat headshield and a narrow trunk covered by brick-like scales. References External links Ateleaspis at PalaeosAteleaspis species location & chronology Osteostraci genera Paleozoic jawless fish Fossils of Norway Fossils of Gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
