Forresteria

Forresteria
Temporal range: Turonian - Coniacian
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Family: Collignoniceratidae
Subfamily: Barroisiceratinae
Genus: Forresteria
Reeside, 1932
Species
  • See text

Forresteria is an extinct genus of cephalopod belonging to the subclass Ammonoidea that flourished during the late Turonian and early Coniacian of the Late Cretaceous.[1] and were global in extent. Forresteria alluaudi and Forresteria hobsoni are considered marker fossils for the lower Coniacian in the American West.

Description

Although the whorl section and ornament of Forresteria are variable, it is easily distinguished from Barroisiceras by the presence of mid-lateral tubercles on the inner whorls, which later disappear or fuse with either umbilical or ventrolateral tubercles. Four subgenera are recognized [2]

Species

species in Forresteria include:


Forresteria was named for Robert Forrester of Salt Lake City, Utah.[1]

References

  1. 1 2 Cobban, William A. et al (2006) "A USGS Zonal Table for the Upper Cretaceous Middle Cenomanian-Maastrichtian of the Western Interior of the United States Based on Ammonites, Inoceramids, and Radiometric Ages" USGS (Open-File Report 2006–1250)
  2. W.J Arkell, et at, 1957 Mesozoic Ammonidea. Treatise on Invertebrate Paleontology, Part L Ammonoidea.
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