Phylloceratina
Encyclopedia
The Phyllocertina comprise a suborder of ammonoid cephalopods, belonging to the Ammonitida
, whose range extends from the Lower Triassic
to the Upper Cretaceous
. Shells of the Phylloceratina are generally smooth with small to large umbilici and complex sutures with leaf-like phylloid saddle endings and lobes with thorn-like projections.
Deineroceratidae, which is though to have given rise early in the Triassic to the Ussuritidae. The Ussuritidae is the ancestral family of the Phylloceratina. The Ussuritidae extend through the Upper Triassic but not into the Jurassic, and gave rise to the Upper Triassic Discophyllitidae. The Discophyllitidae is the probable source for the L Jurassic - U Cretaceous Phylloceratidae and possibly for the L Jurassic Juraphyllitidae.
The Phylloceratina gave rise early in the Jurassic through the Phylloceratidae to the Lytoceratina, which in tern gave rise to most of the Ammonitina The Phylloceratidae also gave rise to the Psilocerataceae at the beginning of the Jurassic and to the Desmocerataceae in the Early Cretaceous, both of which are considered Ammonitina. The Ancyloceratina is a collection of highly evolved Lytoceratina.
Ammonitida
The Ammonitida is an order of more highly evolved ammonoid cephalopods from the Jurassic and Cretaceous time periods, commonly with intricate ammonitic sutures....
, whose range extends from the Lower Triassic
Triassic
The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...
to the Upper Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
. Shells of the Phylloceratina are generally smooth with small to large umbilici and complex sutures with leaf-like phylloid saddle endings and lobes with thorn-like projections.
Phylogeny
The Phylloceratina are most likely derived from the CeratitidCeratitida
The Ceratitida is an order that contains almost all ammonoid cephalopod genera from the Triassic as well as ancestral forms from the Upper Permian, the exception being the phylloceratids which gave rise to the great diversity of post Triassic ammonites....
Deineroceratidae, which is though to have given rise early in the Triassic to the Ussuritidae. The Ussuritidae is the ancestral family of the Phylloceratina. The Ussuritidae extend through the Upper Triassic but not into the Jurassic, and gave rise to the Upper Triassic Discophyllitidae. The Discophyllitidae is the probable source for the L Jurassic - U Cretaceous Phylloceratidae and possibly for the L Jurassic Juraphyllitidae.
The Phylloceratina gave rise early in the Jurassic through the Phylloceratidae to the Lytoceratina, which in tern gave rise to most of the Ammonitina The Phylloceratidae also gave rise to the Psilocerataceae at the beginning of the Jurassic and to the Desmocerataceae in the Early Cretaceous, both of which are considered Ammonitina. The Ancyloceratina is a collection of highly evolved Lytoceratina.