Simoceratinae
Encyclopedia
The Simoceratinae is a subfamily in the Aspidoceratidae
, a family of ammonites in the Perisphinctaceae
, that lived during most of the Late Jurassic, especially in the Pacific and Tethyan realms. Early genera more closely resemble Perisphictidae and have constricted apertures. Later, more aberrant forms are unconstricted and develop grooved or concave venters.
Aspidoceratidae
The Aspidoceratidae comprise a family of middle and upper Jurassic ammonites that make up part of the superfamily Perisphinctaceae, characterized by evolute shells, commonly stocky, that tend to develop tubercles....
, a family of ammonites in the Perisphinctaceae
Perisphinctaceae
Perisphinctoidea, formerly Perisphinctaceae, is a superfamily of Middle Jurassic to Lower Cretaceous ammonites, commonly with evolute shells with strong ribbing that typically divides about mid flank before crossing the venter....
, that lived during most of the Late Jurassic, especially in the Pacific and Tethyan realms. Early genera more closely resemble Perisphictidae and have constricted apertures. Later, more aberrant forms are unconstricted and develop grooved or concave venters.
References
- Arkell, et al, 1957. Mesozoic Ammonoidea. Treatise on Invertebrate Paleontology, Part L. (Ammonoidea). Geol Soc of America and Univ Kansas Press.