''Proclydonautilus'' is a genus of
nautiloids belonging to the
Clydonautilidae
The Clydonautilidae are Middle and Upper Triassic nautiloid cephalopods, which are derivatives of the clydonautiloidean family Liroceratidae, that have generally smooth, involute, globular to compressed shells, characterized by a suture with p ...
known from the Upper Triassic of North America, Europe, and India.
The shell of ''Proclydonautilus'', like those of other Clydonautilitidae, is involute and smooth. It is distinguished by its suture which has a broad, shallow to deep ventral lobe that divides a large ventral saddle. A large lateral lobe on the flans is followed by a small lateral saddle and a second lateral lobe.
With regard to the suture ''Proclydonautilus'' is most similar to ''
Cosmonautilus
''Cosmonautilus'' is a genus of cephalopods included in the nautilid family Clydonautilidae. Its shell is involute, with only the outer whorl exposed. Early whorls are with nodes on ventral shoulder, which disappear on the later growth staged. ...
'' and ''
Callaionautilus
''Callaionautilus'' is a genus of cephalopods included in the nautilid family Clydonautilidae that lived during the Late Triassic. Its fossils have been found on the island of Timor.
The shell of ''Callaionautilus'' is involute, coiled such tha ...
'', both also from the Late Triassic.
References
* Berhard Kummel, 1964. Nautiloidea-Nautilida. Treatise on Invertebrate Paleontology, Part K. Geological Society of America.
Prehistoric nautiloid genera
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