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Birkeniidae
Birkeniidae is an extinct family of jawless fish belonging to the order Birkeniiformes Birkeniiformes (Birkeniida or Birkeniids) is an extinct order of jawless fish belonging to the class Anaspida. Subtaxa A newer taxonomy based on the work of Mikko's Phylogeny Archive, Nelson, Grande and Wilson 2016 and van der Laan 2018. * Ge .... They were defined in 1899 by Ramsay H. Traquair, and were a successful family among the many jawless fish in the Silurian seas. Morphology Birkeniidae had a large body which was ovular in shape, and a strong, mobile tail. Their eyes were positioned on either side of the head. Their mouth was large for the jawless fish, but contained no teeth. Birkeniidae are distinguished by the crown shaped projection on their back, and the other smaller projections which run down its tail. They also possessed fins which faced downwards, an uncommon trait among the jawless fish. They had typical scaly skin. References External links * Prehistoric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saarolepis
''Saarolepis'' is an extinct genus of jawless fish belonging to the family Birkeniidae Birkeniidae is an extinct family of jawless fish belonging to the order Birkeniiformes Birkeniiformes (Birkeniida or Birkeniids) is an extinct order of jawless fish belonging to the class Anaspida. Subtaxa A newer taxonomy based on the work .... References External links * Birkeniiformes genera Fossil taxa described in 1945 {{paleo-jawless-fish-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birkeniiformes
Birkeniiformes (Birkeniida or Birkeniids) is an extinct order of jawless fish belonging to the class Anaspida. Subtaxa A newer taxonomy based on the work of Mikko's Phylogeny Archive, Nelson, Grande and Wilson 2016 and van der Laan 2018. * Genus †''Cowielepis'' Blom 2008 * Genus †'' Hoburgilepis'' Blom, Märss & Miller 2002 * Genus †'' Kerreralepis'' Blom 2012 * Genus †'' Maurylepis'' Blom, Märss & Miller 2002 * Genus †'' Rytidolepis'' Pander 1856 * Genus †'' Schidiosteus'' Pander 1856 * Genus †'' Silmalepis'' Blom, Märss & Miller 2002 * Genus †'' Vesikulepis'' Blom, Märss & Miller 2002 * Family † Pharyngolepididae Kiær 1924 corrig. ** Genus †'' Pharyngolepis'' Kiaer 1911 * Family † Pterygolepididae Obručhev 1964 corrig. ** Genus †'' Pterygolepis'' Cossmann 1920 'Pterolepis'' Kiaer 1911 non Rambur 1838 non De Candolle ex Miquel 1840; ''Pterolepidops'' Fowler 1947 * Family † Rhyncholepididae Kiær 1924 corrig. ** Genus †''Rhyncholepis'' Kiær 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenopleuron
''Ctenopleuron'' is an extinct genus of jawless fish in the class Anaspida Anaspida ("without shield") is an extinct group of primitive jawless vertebrates that lived primarily during the Silurian period, and became extinct soon after the start of the Devonian. They were classically regarded as the ancestors of lampre .... References External links * Birkeniiformes genera Fossil taxa described in 1907 {{paleo-jawless-fish-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birkenia
''Birkenia'' is a genus of extinct anaspid fish from Middle Silurian strata of Northern Europe, and Middle Silurian to possibly Earliest Devonian strata of Arctic Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ....Blom, Henning, T. Märss, and C. G. Miller. "Silurian and earliest Devonian birkeniid anaspids from the Northern Hemisphere." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 92.03 (2001): 263-323/ref> Birkeniid anaspids are covered by a series of small plates on the head and rod-shaped scales in a cheveron-like pattern on the trunk. Intact fossil specimens of ''B. elegans'' suggest the living animal reached a length of up to , and was an active swimmer. In addition to whole specimens and scale microfossils of ''B. elegans'', which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Jawless Fish Families
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
