Morrowites

Morrowites
Temporal range: Turonian 94.3–89.3 Ma
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Family: Acanthoceratidae
Subfamily: Mammitinae
Genus: Morrowites
Cobban & Hook, 1983
Species
  • M. depressus
  • M. dixeyi
  • M. subdepressus
  • M. wingi

Morrowites, named by Cobban and Hook, 1983, is a moderate to large-sized ammonite with quadrangular to depressed whorls, broadly rounded to depressed venter, low ribs, umbilical and inner and outer ventrolateral tubercles and smooth early whorls except for occasional ribs along weak constrictions. The suture is moderately simple and has an unusually broad bifid first lateral lobe. It is so far restricted to the Lower Turonian stage, in the mid Cretaceous.

Morrowites closely resembles Mammites, however Morrowites has a broad first lateral lobe, Mammites has a narrow one. The very early whorls of Morrowites are smooth except for distantly placed ribs and constrictions, those of Mammites have normal ribs and tubercles.