Alocolytoceras is a lytoceratid ammonite with whorls that pass during growth from round to oval, rounded-quadrate, or compressed; with about 19 deep constrictions per whorl, with as many as 21 sharp ribs in between. The shell is evolute. All whorls are visible from either side.

Alocolytoceras
Temporal range: Toarcian[1]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Family: Lytoceratidae
Subfamily: Alocolytoceratinae
Genus: Alocolytoceras
Hyatt, 1900[2]

Alocolytoceras belongs to the lytoceratid subfamily Alocolytoceratinae, which also includes Pachylytoceras and Pleurolytoceras. It is known from the upper Lower Jurassic of Europe and the Himalaya.

References edit

Notes
  1. ^ Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Cephalopoda entry)". Bulletins of American Paleontology. 363: 1–560. Archived from the original on 2016-02-25. Retrieved 2017-10-18.
  2. ^ "Paleobiology Database - Alocolytoceras". Retrieved 2017-10-19.
Bibliography
  • Arkell, W.J.; Kummel, B.; Wright, C.W. (1957). Mesozoic Ammonoidea. Treatise on Invertebrate Paleontology, Part L, Mollusca 4. Lawrence, Kansas: Geological Society of America and University of Kansas Press.