Perisphinctoidea, formerly Perisphinctaceae, is a superfamily of Middle Jurassic (Bajocian) to Lower Cretaceous (Barremian) ammonites, commonly with evolute shells with strong ribbing that typically divides about mid flank before crossing the venter.
Perisphinctoidea, formerly Perisphinctaceae, is a superfamily of Middle Jurassic (Bajocian) to Lower Cretaceous (Barremian) ammonites, commonly with evolute shells with strong ribbing that typically divides about mid flank before crossing the venter.
==Classification== Some 16 families have been recognized in the Perisphinctoidea. The following is based on Donovan et al. 1981 with modification from the Treatise on Invertebrate Paleontology, Part L (1957) Perisphinctidae: Middle and Upper Jurassic root stock, derived from the Stephanoceratidae
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).