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).
Alocolytoceratinae Temporal range:
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | †Ammonoidea |
Order: | †Ammonitida |
Family: | †Lytoceratidae |
Subfamily: | †Alocolytoceratinae Spath,1927 |
Genera[1] | |
Alcolytocerainae includes Alocolytoceras, Lobolytoceras, Pachylytocras, and Pleurolytoceras, which are mostly from the Toarcian. One genus, Pachylotoceras, extends into the lower Bajocian.
References
edit- Notes
- ^ Paleobiology Database - Alocolytoceratinae. 2014-05-29.
- Bibliography
- W.J.Arkell, B.Kummel, & C.W.Wright 1957. Mesozoic Ammonoidea, Treatise on Invertebrate Paleontology, Part L Ammonoidea. R.C.Moore, (ed).