| advertise add site services publishers database health videos | ![]() | about toolbar stats live show health store more stuff JOIN/LOGIN |
The Phylloceratina suborder of ammonites are a group extending from the Lower Triassic to Upper Cretaceous periods. They are typically robust with strongly expanding whorls, small umbilici, and highly fractally ornate suture lines. It appears that all other Jurassic and Cretaceous ammonites (Ammonitina, Lytoceratina, Ancyloceratina) must have arisen from the Phylloceratina, since among these ammonitides only Phylloceratina are present from the early Triassic period onward.
| ||||||||||||||||||||||
| ↑ top of page ↑ | about thumbshots |