Alocolytoceratinae

From Wikipedia, the free encyclopedia

Alocolytoceratinae
Temporal range: Toarcian–Bajocian
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Family: Lytoceratidae
Subfamily: Alocolytoceratinae
Spath,1927
Genera[1]

Alocolytoceratinae is a subfamily of lytoceratids that comprises genera characterized by many deep constrictions in the shell resulting in capricorn-like (goat's horm) ornamention, especially in the middle whorls, but becoming smooth and more involute in the outer whorls. Saddle endings in the suture tend to be phylloid, (leaf-like).

Alcolytocerainae includes Alocolytoceras, Lobolytoceras, Pachylytocras, and Pleurolytoceras, which are mostly from the Toarcian. One genus, Pachylotoceras, extends into the lower Bajocian.

References[edit]

Notes
Bibliography