Cephalopoda - Nautilida - Liroceratidae
Alternative combinations: Parapenascoceras rotundatum, Titanoceras rotundatum
Full reference: A. K. Miller and A. G. Unklesbay. 1942. Permian nautiloids from western United States. Journal of Paleontology 16(6):719-738
Belongs to Stearoceras according to P. L. Sealey and S. G. Lucas 2025
See also Miller and Unklesbay 1942, Miller and Youngquist 1949 and Ruzhentsev and Shimanskiy 1954
Sister taxa: Stearoceras conchiferum, Stearoceras gibbosum, Stearoceras hesperium, Stearoceras immane, Stearoceras involutum, Stearoceras militarium, Stearoceras milleri, Stearoceras phosphoriense, Stearoceras punjabicum, Stearoceras sanandreasense, Stearoceras simplex, Stearoceras smithi, Stearoceras sublaeve
Type specimen: Its type locality is Penasco Valley, Highway 82, which is in a Kungurian shallow subtidal limestone in the San Andres Formation of New Mexico
Ecology: nektobenthic carnivore
Average measurements (in mm): shell diameter 81.8
Distribution:
• Permian of United States (9: Arizona, New Mexico collections)
Total: 9 collections each including a single occurrence
Specimen images are retrieved through the ePANDDA API.
Click image to enlarge. Click to access iDigBio record.