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Alocolytoceratinae

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.