Doulingoceras
Encyclopedia


Doulingoceras is a genus of ammonoid within the ceratitid
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....

 order, found in China,that lived during the Late Permian during the time span from about 260.5 to 254 million years ago. The genus is included in the family Paraceltitidae
Paraceltitidae
Paraceltitidae is a family of Middle and Upper Permian cephalopods, that comprise the earliest of the Ceratitida. Paraceltitidids have variably ribbed, discoidaly evolute shells with compressed elliptical whorl sections and simple suture lines. Their origin is most likely in the Daraelitidae of...

, which belongs to the superfamily Xenodiscaceae
Xenodiscaceae
The Xenodiscaceae is a superfamily within the ammonoid order Ceratitida. The Xenodiscaceae, named by Frech in 1902, presently contains ten families, only one of which was included in the original Otocerataceae of Hyatt, 1900, the remaining having been added.The Xenodiscaceae has its origin in the...

.

Doulingoceras produced a narrowly discoidal evolute shell with concave sides, a narrowly rounded rim (venter) that bears several longitudinal lirae, and transverse rigs that have nodes at the umbilical and ventrolateral shoulders that form spiral belts. The suture is identical to that of Paraceltites
Paraceltites
Paraceltites is an ammonoid cephalopod genus in the ceratitid family Paraceltitidae, known from the Middle and Upper Permian of Sicily, the Alps, Crimea, Texas and Mexico. The shell of Paraceltities is evolute with whorls compressed, venter arched and smooth, sides bearing ribs that slant somewhat...

in which the lobes are unserrated.

Doulingoceras closely resembles Paraceltites in the shape of shell and suture; but it may be distinguished from the latter by the concave sides and the node-like transverse ribs in the early stage and two rows of nodes distributed respectively along the ventral edge and the umbilical shoulder at maturity.

The type species, Doulingoceras nodosum, named by Zhou, 1985, was originally found in black marine mudstone in the Douling Formation in Hunan Provence, China.
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