Mammites
Mammites Temporal range: Turonian | |
---|---|
M. nodosoides fossil from Madagascar | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | Ammonoidea |
Order: | Ammonitida |
Superfamily: | Acanthoceratoidea |
Family: | Acanthoceratidae |
Subfamily: | Mammitinae |
Genus: | Mammites Laube and Bruder, 1887 |
Species | |
see text |
Mammites is an Upper Cretaceous ammonite genus included in the acanthoceratoidean family, Acanthoceratidae, and the type genus for the subfamily Mammitinae. Mammites, which is restricted to the Turonian (99.7 to 89.3 Ma), was named by Laube and Bruder in 1887. [1][2]
Species
Species within the genus Mammites include: [2]
- M. mohavanensis Böse 1923. Found at Loma el Macho, Coahuila, Mexico.
- M. mutabilis Reyment 1955. Known from Cameroon.
- M. nodosoides Schlüter 1871. Found in North and South America, Africa and Europe.
- M. powelli Kennedy et al. 1987. Found in Texas and Columbia
- M. rancheriae Anderson 1958. Known from the North American pacific region.
Description
Shells of Mammites are typically stout, usually with a rectangular or squarish whorl section and flattish to slightly concave venter and can reach a diameter of 15–20 millimeters (0.59–0.79 in). Ornamentation is dominated by strong umbilical tubercles and moderate inner and outer ventrolateral tubercles. Ribs are somewhat prominent in juveniles stages but tend to become inconspicuous in the adult. The suture is ammonitic but rather simple. Some species, those with broad first lateral lobes in the suture, have been reassigned to Morrowites
Mammites and Morrowites are rather similar except that Mammites as redefined has a narrow first later lobe while that in Morrowites is broad and the early whorls in Morrowites are smooth except for widely spaced ribs and constrictions while those in Mammites have normal ribs and tubercles.
Distribution
Fossils of species within this genus have been found in the Cretaceous sediments of Angola, Brazil, Cameroon, Colombia, Egypt, France, India, Madagascar, Mexico, Nigeria, Peru, Romania, Tunisia, United States and Venezuela.[2]
References
- Arkell et al., 1957, Mesozoic Ammonoidea, Treatise on Invertebrate Paleontology Part L. Geological Soc. of America, Univ of Kansas Press. R.C. Moore, (Ed)
- W. A. Cobban and Hook, S. C. 1983 Mid-Cretaceous (Turonian) ammonite fauna from Fence Lake area of west-central New Mexico. Memoir 41, New Mexico Bureau of Mines&Mineral Resources, Socorro NM.
- W. A. Cobban and Hook, S. C. 1979, Collignoniceras woollgari wooollgari (Mantell) ammonite fauna from Upper Cretaceous of Western Interior, United States. Memoir 37, New Mexico Bureau of Mines&Mineral Resources, Socorro NM.