Xenoceltitidae
Encyclopedia
Xenoceltitidae are evolute, generally ribbed, upper Lower Triassic
Ceratitida
with ceratitic or goniatitic sutures; formerly included in the Noritaceae but now placed in the Xenodiscaceae.
The Xenoceltitidae are derived from the Ophiceratidae
.
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...
Ceratitida
Ceratitida
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....
with ceratitic or goniatitic sutures; formerly included in the Noritaceae but now placed in the Xenodiscaceae.
The Xenoceltitidae are derived from the Ophiceratidae
Ophiceratidae
The Ophiceratidae is a family in the ammonoid order Ceratitida from the Lower Triassic, previously included in the Otocerataceae but now placed in the Noritiaceae as revised....
.