Nannolytoceras
Nannolytoceras is an extinct genus of lytoceratid ammonite, family Lytoceratidae, with a stratigraphic range extending from the Bajocian age to Bathonian age (Medium Jurassic).[1] DescriptionShells of Nannolytoceras species reach a diameter of about 46–75 millimetres (1.8–3.0 in).[2][3] The shell is evolute, smooth, tubular to compressed, with a variable number of more or less regularly spaced deep constrictions.[3] The very thin ribs crossing the ventral region are barely visible. Umbilicus is relatively large. The suture line is of ammonitic type.[4] These cephalopods were fast-moving nektonic carnivores.[5] DistributionFossils of species within this genus have been found in the Jurassic rocks of Italy, Spain,[5] Slovakia,[6] and France.[7] References
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