Transicoeloceras

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Transicoeloceras
Temporal range: Toarcian [1]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Family: Dactylioceratidae
Subfamily: Nodicoeloceratinae
Genus: Transicoeloceras
Pinna, 1966
Type species
Transicoeloceras angustum
Pinna, 1966
Species
  • T. angustum Pinna, 1966
  • T. viallii Pinna, 1966
  • T. ramaccionii Pinna, 1966

Transicoeloceras, which is sometimes considered to be a synonym of Catacoeloceras[2] is genus of ammonite that lived during Toarcian stage (Bifrons to lower Gradatus ammonite Zones) of early Jurassic. Their fossils were found in Hungary, Italy, France, southern Spain and South America. It has evolved from Mesodactylites.[1]

Description[edit]

Ammonites belonging to this genus have small shells. Coiling is involute to sphaerocone. Rounded subtrapezoid whorl section has maximum width at the shoulder. Umbilicus is deep and venter is broad and convex. Fine ribs were simple, or bifurcating and also had tubercules.[1]

References[edit]

  1. ^ a b c Kovács, Z. (2014). Toarcian Dactylioceratidae (Ammonitina) from the Gerecse Mts (Hungary). Hantkeniana, 9, 45-77.
  2. ^ M. K. Howarth 2013. Treatise on Invertebrate Paleontology, Part L, Revised, Volume 3B, Chapter 4: Psiloceratoidea, Eoderoceratoidea, Hildoceratoidea.