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Cephalaspis Tenuicornis
''Cephalaspis'' (from , 'head' and , 'shield') is a possibly monotypic taxon, monotypic Genus (biology), genus of extinct Osteostraci, osteostracan agnathan vertebrate. It was a trout-sized detritivorous fish that lived in the early Devonian. Description Like its relatives, ''Cephalaspis'' was heavily armored, presumably to defend against predatory placoderms and eurypterids, as well as to serve as a source of calcium for metabolic functions in calcium-poor freshwater environments. It had sensory patches along the rim and center of its head shield, which were used to sense for worms and other burrowing organisms in the mud. Diet Because its mouth was situated directly beneath its head, ''Cephalaspis'' was thought of as being a bottom-feeder, akin to a heavily armoured catfish or sturgeon. It moved its plow-like head from side to side, ''Cephalaspis'' easily stirring sand and dust into the water, along with revealing the hiding places of its prey, digging up worms or crustacean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Devonian
The Early Devonian is the first of three Epoch (geology), epochs comprising the Devonian period, corresponding to the Lower Devonian Series (stratigraphy), series. It lasted from and began with the Lochkovian Stage , which was followed by the Pragian from and then by the Emsian, which lasted until the Middle Devonian began, . During this time, the first Ammonoidea, ammonoids appeared, descending from Bactritida, bactritoid Nautiloidea, nautiloids. Ammonoids during this time period were simple and differed little from their nautiloid counterparts. These ammonoids belong to the order Agoniatitida, which in later epochs evolved to new ammonoid orders, for example Goniatite, Goniatitida and Clymeniida. This class of cephalopod molluscs would dominate the marine fauna until the beginning of the Mesozoic Era. References Early Devonian, Geological epochs Devonian geochronology, *01 {{Geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
