The Aspidoceratinae is a subfamily in the perisphictacean ammonite family,

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 thought ...

found world wide in middle and upper

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

sediments. Aspidoceratinae differ from Peltoceratinae in that the early biplicate ribbed stage is lacking, or greatly reduced, and no forms with lappets are known. Aptycus are bivalved and very durable, and in the "lower Kimmeridgian form Aptychus beds, containing few or no ammonites". (Kimmeridgian is middle Upper Jurassic, follows the Oxfordian and predates the Tithonian). The earliest Aspidoceratinae occur with the first Peltoceratinae, and likewise are probably derived from within the

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 aperture ...

References

;Notes ;Bibliography * Arkell, et al., 1957. Mesozoic Ammonoidea.

Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology,'' published from 1953–2007 by the Geological Society of America and the University of Kansas, then 2009–present by the University of Kansas Paleontological Institute, is a definitive multi-authore ...

, Part L (Ammonoidea). Geol Soc of America and Univ Kansas Press. Jurassic ammonites Aspidoceratidae {{Ammonitina-stub