Polyptychites

Polyptychites
Temporal range: Early Cretaceous (Valanginian)
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Superfamily: Perisphinctaceae
Family: Polyptichitidae
Genus: Polyptichites

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.

References

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