Polyptichites is the perisphictacean ammonite genus from the Lower Cretaceous of Russia. The shell is subinvolute and coarsely ribbed; ribs bifurcate or trifurcate mid or low on the flanks and cross over the rounded venter. The umbilicus is relatively small and deep. Outer whorls partially envelop the previous leaving a fairly deeply impressed dorsum.

• Polyptichites, jsdammonites.fr

This prehistoric cephalopod-related article is a stub. You can help Wikipedia by expanding it.

• v
• t
• e