''Doulingoceras'' is a genus of

ammonoid Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...

within the

ceratitid 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 ammon ...

order, found in China, that lived during the

Late Permian Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudonym used by Dave Groh ...

during the time span from about 260.5 to 254 million years ago. The genus is included in the family

Paraceltitidae Paraceltitidae is a family of Middle Permian, Middle and Upper Permian cephalopods, that comprise the earliest of the Ceratitida. Paraceltitidids have variably ribbed, discoidally evolute shells with compressed elliptical whorl sections and simpl ...

, which belongs to the superfamily

Xenodiscaceae Xenodiscoidea, formerly Xenodiscaceae, is a superfamily within the ammonoid order Ceratitida. The superfamily was named by Frech in 1902, presently contains ten families, only one of which was included in the original Otocerataceae of Hyatt, 190 ...

. ''Doulingo""ceras'' 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'' is a genus of ammonoid cephalopods 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 compresse ...

'' 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.

Species

According to GONIAT.org there are 2 species; they are: *''Doulingoceras costituberosum'' *''Doulingoceras nodosum'' (

Type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

)

References

GONIAT-online ''Doulingoceras'' entryThe Paleobiology Database ''Doulingoceras'' entry
Paraceltitidae Permian ammonites Ceratitida genera Permian animals of Asia Permian China {{Ceratitida-stub