Phoenixites

Phoenixites
Temporal range: Late Devonian
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Goniatitida
Family: Tornoceratidae
Subfamily: Falcitornoceratinae
Genus: Phoenixites
Becker, 1995
Species
  • See text

Phoenixites is an early (Late Devonian), genus of the Falcitornoceratinae, a subfamily of the goniatitid Tornoceratidae family. This genus was named by Becker in 1995. The type species is "Tornoceras" frechi.

The shell of Phoenixites is discoidal, on which constrictions may be present. Growth lines are strongly biconvex in juvenile stages, later with shallow a lateral sinus.

Phoenixites may have contained the ancestor of Falcitornoceras which likely gave rise to Gundolficeras, all members of the Falcitornoceratinae.

Biostratigraphic significance

The International Commission on Stratigraphy (ICS) has assigned the First Appearance Datum of Phoenixites frechi as the defining biological marker for the start of the Famennian Stage, 372.2 ± 1.6 million years ago, the final stage of the Devonian. This lower limit is also defined by the Upper Kellwasser Extinction, when the conodont genera Ancyrodella, and Ozarkodina and many species of Palmatolepis, Polygnathus, and Ancyrognathus disappeared.


References

This article is issued from Wikipedia - version of the Monday, May 02, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.