Perisphinctoidea, formerly Perisphinctaceae, is a superfamily of Middle Jurassic (Bajocian) to

Lower Cretaceous Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Lower Wick is a small hamlet located in the county of Gloucestershire, England. It is situated about five miles south west of Dursley, eigh ...

(Barremian)

ammonites Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

, 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.'' 1981Donovan, Callomon and Howarth 1981 Classification of the Jurassic Ammonitina; Systematics Association. with modification from the Treatise on Invertebrate Paleontology, Part L (1957) *

Perisphinctidae Perisphinctidae is a family of Middle and Upper Jurassic discoidal ammonites in the order Ammonitida. They have a shell morphology that is mostly evolute, typically with biplicate, simple, or triplicate ribbing. Large forms have simple apertur ...

: Middle and Upper Jurassic root stock, derived from the

Stephanoceratidae Stephanoceratidae is a family of planulate and coronate ammonites within the Stephanoceratoidea.Arkell, Kummel, and Wright, 1957. Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L, Mollusca 4. Shells are evolute so that all whorl ...

(Middle Jurassic direct derivatives of the Perisphinctidae) * Morphiceratidae * Tulitidae *

Reineckeiidae Reineckeiidae is an extinct ammonoid cephalopod family belonging to the superfamily Perisphinctoidea. These fast-moving nektonic carnivores lived during the Jurassic period, from the Callovian In the geologic timescale, the Callovian is an a ...

* Pachyceratidae *

Aspidoceratidae The Aspidoceratidae comprise a family of middle and upper Jurassic ammonites that make up part of the superfamily Perisphinctoidea, characterized by evolute shells, commonly stocky, that tend to develop tubercles. The Aspidoceratidae are thoug ...

(early Upper Jurassic (Oxfordian) derivatives of Perisphinctidae) * Aulacostephanidae * Ataxioceratidae (mid Upper Jurassic (Kimmeridgian) derivatives of the Ataxioceratidae) * Dorsoplanitidae * Virgatitidae (late Upper Jurassic (Tithonian) derivatives of Perisphinctidae) * Simoceratidae * Himalayitidae * Olcostephanidae *

Holcodiscidae Holcodiscidae is an ammonite family placed in the superfamily Desmoceratoidea. Berriasellidae (derived from Ataxioceratidae)(now considered a subfamily of Neocomitidae) * Polytichitidae Craspeditidae.html" ;"title="Craspeditidae.html" ;"title="Craspeditidae">Craspeditidae">Craspeditidae.html" ;"title="Craspeditidae">Craspeditidae(derived from Dorsoplanitidae) *Neocomitidae (derived from Berriasellidae)(now placed in the superfamily Endemoceratoidea) *Oosterellidae (Hauterivian derivative of the Neocomitidae)

References

Perisphinctoidea, Ammonitina Prehistoric animal superfamilies Bajocian first appearances Early Cretaceous extinctions {{ammonitina-stub