Balticeras Explained

Balticeras is an involute, discoidal Upper Jurassic (Oxfordian) ammonite[1] (order Ammonitida) found in England, Germany, and Switzerland, belonging to the Perisphinctidae. The shell is strongly embracing, tending to be oxyconic (sharp rimmed). Sides are gently curved, converging on a narrow to sharp ventral rim.

Balticeras is considered by some to be a subgenus of Ringsteadia which in contrast is more evolute, with ribbed inner whorls. Both are included in the Pictoniinae, a subfamily established by Spath, 1924, for large ammonites within the Perisphinctidae, tending to develop smooth middle and outer whorls.

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  • Notes and References

    1. Web site: Sepkoski. Jack. Sepkoski's Online Genus Database. 2002. 2014-05-28 .