Holoptychius

Holoptychius was a streamlined predator about long (though largest specimen could grow up to ), which fed on other bony fish. Its rounded scales and body form indicate that it could have swum quickly through the water to catch prey. Similar to other rhipidistians, it had fang-like teeth on its palate in addition to smaller teeth on the jaws. Its asymmetrical tail sported a caudal fin on its lower end. To compensate for the downward push caused by this fin placement, the pectoral fins of Holoptychius were placed high on the body. == Species ==

Of the genus Holoptychius the following species have been described: • H. americanus • H. andersoni • H. bergmanni (Downs et al., 2013) from the Frasnian-aged Fram Formation of Ellesmere Island, Arctic Canada • H. flemingi • H. giganteus • H. halli • H. hopkinsii • H. nobilissimus • H. quebecensis • '''H. sp. indet.''' from the Kennebecasis Formation of New Brunswick, Canada. • '''H. sp. indet.''' from the Cuche Formation of Colombia, known from an isolated tooth (UN-DG-PALV86) and preserved scales (UN-DG-PALV50-51). == Distribution ==

Fossils of Holoptychius have been found in the Mississippian of the United Kingdom and the Devonian of Belgium, Colombia (Cuche Formation, Boyacá), == Palaeoecology ==

Isotopic analysis of Holoptychius remains from Greenland reveals that it was likely a euryhaline organism. == Gallery ==

File:Holoptychius andersoni.jpg|H. andersoni File:Holoptychius sp. 2.jpg|Life restoration of Holoptychius sp. File:Holoptychius nobilissimus.jpg|H. nobilissimus and scale == References ==