The Pseudotriolitidae is a family of xenodiscaean ceratitid ammonoids established by Zhao, 1956, that lived during the Late Permian and Early Triassic and have been found in China, Thailand, Azerbaijan, and Iran. Genera included for sure are Pseudotirolites (type)and Schizoloboceras. Other genera which may be included are Chaolianoceras, Dushanoceras, Pachydiscoceras, Permococeras, and Trigonogastrites. With the exception of Pseudotirolites which was named by Sun, 1939, all the others were named by Zhao and Liang between 1966 and 1978.
Pseudotirolitidae are characterized by evolute discoidal shells with a pentagonal, suboval or rectangular whorl section , fastigate venter and keel, and wide shallow umbilicus. Sides are sculptured with transverse ribs and ventro-lateral nodes. Suture is ceratitic.
Credits: JM 6/02/12