''Antigyroceras'' is a genus of

nautiloid Nautiloids are a group of cephalopods (Mollusca) which originated in the Late Cambrian and are represented today by the living ''Nautilus'' and ''Allonautilus''. Fossil nautiloids are diverse and species rich, with over 2,500 recorded species. Th ...

s in the order

Discosorida Discosorida are an order of cephalopods that lived from the beginning of the Middle Ordovician, through the Silurian, and into the Devonian. Discosorids are unique in the structure and formation of the siphuncle, the tube that runs through and co ...

, known from central Asia, that lived during Late

Silurian The Silurian ( ) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the third and shortest period of t ...

and Early

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

times. It is contemporary with the discosorid '' Endoplectoceras.''

References

* Sepkoski, J.J. Jr. 2002. A compendium of fossil marine animal genera. D.J. Jablonski & M.L. Foote (eds.). ''Bulletins of American Paleontology'' 363: 1–560
Sepkoski's Online Genus Database (CEPHALOPODA)
* ''Antigyroceras'' in Fossilworks gatewa

Prehistoric nautiloid genera Silurian first appearances Early Devonian genus extinctions Discosorida {{paleo-Nautiloidea-stub