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Bitaunioceras

Bitaunioceras is a Permian orthocerid with a gradually expanding, straight, orthoconic shell with straight transverse sutures and a small, subcentral siphuncle with staight tubular orthochoamitic necks.

The shell surface of Bitaunioceras has a few, shallow, rounded constrictions and numerous, unequal, prominent transverse wire-like lirae.

Bitaunioceras species have been found in Texas in the United States, Coahuila in Mexico, Sicily, Timor, and the south Urals in Russia.