Pycnodontiformes
Encyclopedia
Pycnodontiformes is an extinct order of bony fish. The group evolved during the Late Triassic
and disappeared during the Eocene
. The group has been found in rock formations in Africa, Asia, Europe, North and South America.
The pycnodontiforms were small to middle-sized fish, with laterally-compressed body and almost circular outline.
Pycnodontiform fishes lived mostly in shallow-water seas. They had special jaws with round and flattened teeth,. well adapted to crush food items. One study links the dentine tubules in pycnodont teeth to comparable structures in the dermal denticles of "Cambro-Ordovician ostracoderm fish.
" (sic) Some species lived in rivers and possibly fed on molluscs and crustaceans.
Late Triassic
The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...
and disappeared during the Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
. The group has been found in rock formations in Africa, Asia, Europe, North and South America.
The pycnodontiforms were small to middle-sized fish, with laterally-compressed body and almost circular outline.
Pycnodontiform fishes lived mostly in shallow-water seas. They had special jaws with round and flattened teeth,. well adapted to crush food items. One study links the dentine tubules in pycnodont teeth to comparable structures in the dermal denticles of "Cambro-Ordovician ostracoderm fish.
Astraspis
Astraspis is an extinct genus of primitive jawless fish from the Ordovician of Central North America and Bolivia . It is related to other Ordovician fishes, such as the South American Sacabambaspis, and the Australian Arandaspis.-Basic Anatomy:Astraspids are hypothesized to have been about 200mm...
" (sic) Some species lived in rivers and possibly fed on molluscs and crustaceans.
Taxonomy
- †Order Pycnodontiformes (Berg, 1937)
- †Paramesturus
- †MesturusMesturusMesturus is an extinct genus of bony fish....
- †MicropycnodonMicropycnodonMicropycnodon is an extinct genus of prehistoric bony fish that lived during the Santonian.-See also:* Prehistoric fish* List of prehistoric bony fish...
- †GyrodusGyrodusGyrodus is an extinct genus of pycnodontiform bony fish that lived in the Jurassic and Cretaceous....
- †Arduafrons
- †EomesodonEomesodonEomesodon is an extinct genus of prehistoric bony fish.-See also:* Prehistoric fish* List of prehistoric bony fish...
- Family †Brembodontidae, Tintori 1981
- Family †Coccodontidae, Berg, 1940
- †CoccodusCoccodusCoccodus is an extinct genus of extinct pycnodontid fish that lived during the lower Cenomanian. The various species had a pair of massive, curved spines emanating from the lower sides of the head, and one curved spine on the top of its head...
- †Hensodon
- †Coccodus
- Family †Trewavasiidae, Nursall and Capasso 2008
- †TrewavasiaTrewavasiaTrewavasia carinata is an extinct pycnodontid that lived during the lower Cenomanian of what is now Lebanon. It had a large, forward-pointing horn-like spine between its eyes, and a massive stump-like spine emanating from the . T...
- †Ichthyoceros
- †Trewavasia
- Family †Pycnodontidae, Agassiz 1833
- †Akromystax
- †Macromesodon
- †Stenamara
- †StemmatodusStemmatodusStemmatodus is an extinct genus of prehistoric bony fish that lived during the Early Cretaceous epoch.-See also:* List of prehistoric bony fish* Prehistoric fish...
- †Turbomesodon
- †Anomoedus
- †Ocloedus
- †Tepexichtys
- †Neoproseinetes
- †ProscinetesProscinetesProscinetes is an extinct genus of prehistoric bony fish.-See also:* Prehistoric fish* List of prehistoric bony fish...
- †Tamanja
- †Potiguara
- †CoelodusCoelodusCoelodus is an extinct genus of prehistoric bony fish.-See also:* Prehistoric fish* List of prehistoric bony fish...
- †PycnodusPycnodusPycnodus is an extinct genus of ray-finned fish ranging from the Cretaceous to Eocene periods. As its name suggests, it is the type genus of Pycnodontiformes....
- †Oropycnodus
- †NursalliaNursalliaNursallia is an extinct genus of bony fish from the Late Cretaceous period. It is often referred to as "dinner-plate fish" because of its shape and size.-References:...
- †Abdobalistum
- †PalaeobalistumPalaeobalistumPalaeobalistum is an extinct genus of prehistoric bony fish.-See also:* Prehistoric fish* List of prehistoric bony fish-External links:*...