extinct genus of very primitive jawless, fishlike vertebrates found in Early Devonian rocks (the Devonian Period lasted from 408 to 360 million years ago) in Europe and North America. Cephalaspis, one of an early group of vertebrates called ostracoderms, possessed an external bony head shield, but probably its internal skeleton was not ossified to any great extent. Its eyes were situated on the dorsal side of the flat head; the ventral placement of its mouth indicates that Cephalaspis was a bottom-feeding animal. It is probable that Cephalaspis lived by straining organic matter from the bottom sediments of the freshwater streams it inhabited, a feeding method that persisted from its ancestors. Cephalaspis differed from its predecessors in that the head shield was freed from the rest of the body, allowing for greater mobility, and it also possessed paired pectoral fins. Sensory structures, perhaps electric organs of a sort, were present along the margins of the head shield. See also ostracoderm. (ostracoderm)

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Universalium. 2010.

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  • Cephalaspis — Temporal range: Early Devonian 415–398 Ma …   Wikipedia

  • Cephalaspis — Fossil von Cephalaspis im Aquazoo – Löbbecke Museum in Düsseldorf Zeitraum Unterdevon 418,1 bis 391,9 Mio. Jahre Fundorte …   Deutsch Wikipedia

  • Cephalaspis — Cephalaspis …   Wikipédia en Français

  • Cephalaspis — Saltar a navegación, búsqueda ? Cephalaspis Rango fósil: Devónico …   Wikipedia Español

  • Cephalaspis — Ceph a*las pis, n. [NL., fr. Gr. kefalh head + ? a shield.] (Paleon.) A genus of fossil ganoid fishes found in the old red sandstone or Devonian formation. The head is large, and protected by a broad shield shaped helmet prolonged behind into two …   The Collaborative International Dictionary of English

  • Cephalaspis — Cephalaspis, s. Fische …   Meyers Großes Konversations-Lexikon

  • Cephalaspis — Cephalaspis …   Wikipédia en Français

  • Cephalaspis — Cephalạspis   [zu griechisch kephale̅ »Kopf« und aspís »eine giftige Schlange«], Gattung ausgestorbener, bis 60 cm langer fischähnlicher Wirbeltiere aus dem Unterdevon Spitzbergens, Mitteleuropas und Nordamerikas, mit einheitlichem Kopfschild;… …   Universal-Lexikon

  • cephalaspis — ceph·a·las·pis …   English syllables

  • cephalaspis — pə̇s noun Usage: capitalized Etymology: New Latin, from cephal + aspis : a genus (the type of the family Cephalaspidae) of Devonian ostracoderms having the head covered by a flattened shield rounded in front and prolonged into posteriorly… …   Useful english dictionary

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