Evolution and biogeography of the Cenomanian (Upper Cretaceous) ammonite Metoicoceras Hyatt, 1903, with a revision of Metoicoceras praecox Haas, 1949

Journal article

Five chronologic species can be recognized in Wyoming (from oldest to youngest): M. sp. A, M. praecox Haas, M. frontierense Cobban, M. mosbyense Cobban, and M. geslinianum (d'Orbigny). Metoicoceras praecox, which is described in detail, has several features in common with M. latoventer Stephenson, a middle Cenomanian species known from the Gulf Coast region. Early members of the lineage are known from a limited area in Texas, but, during the early part of the late Cenomanian, members of the genus spread throughout the Western Interior. The latest species, M. geslinianum (d'Orbigny), migrated out beyond the Western Interior during the late Cenomanian Sciponoceras gracile zone and became an important international guide fossil known from the Western Interior and Gulf Coast region, Mexico, Brazil, Africa, western Europe, Israel, Iran, and the USSR. -from Authors

Authors: Cobban, W; Kennedy, W

• Journal: US Geological Survey Bulletin
• Volume: 1934
• Publication date: 1991-01-01
• ISSN: 0083-1093
• Language: English