Calocyrtoceras is a genus of orthocerids (Cephalopoda, Nautiloidea), from the middle Silurian of North America (Quebec) and central Europe.

Calocyrtoceras
Temporal range: Middle Silurian
Scientific classification
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Calocyrtoceras

Foerste 1936

The shell, or conch, of Calocyrtoceras is generally characteristic of its family, the Paraphragmitidae, an annulated cyrtocone. In the case of Calocyrtoceras striated both transversely and longitudinally.

Similar Cyrtocycloceras from the Middle Silurian of Europe is only striated transversely while similar Gaspocyclocas from the Middle Silurian of North America is only striated longitudinally.

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