Hoploscaphites

Hoploscaphites is an extinct ammonite genus from the Upper Cretaceous and the Lower Paleocene, included in the family Scaphitidae.

Hoploscaphites Temporal range: Upper Cretaceous to Lower Paleocene
Hoploscaphites; Pierre Shale. South Dakota
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	†Ammonoidea
Order:	†Ammonitida
Suborder:	†Ancyloceratina
Family:	†Scaphitidae
Subfamily:	†Scaphitinae
Genus:	†Hoploscaphites Nowak, 1911
Species
See text

Morphology

It is considered by some to be a subgenus of Scaphites. Like Scaphites, the shell of Hoploscaphites is involute with the final whorl projecting forward and curving back on itself. Shells vary from compressed to inflated with convex sides. Tubercles normally present may be sparse or absent.

Distribution

Fossils of Hoploscaphites have been found in Antarctica, Austria, Belgium, Bulgaria, Canada (Alberta, Saskatchewan), Chile, Denmark, France, Germany, Greenland, India, the Netherlands, Turkmenistan, Ukraine and the United States (Arkansas, Colorado, Delaware, Kansas, New Jersey, New Mexico, North Dakota, South Dakota, Texas, Wyoming).^[1] Of the few genera of ammonites which are thought to have survived the K-Pg extinction event into the Danian period (65-61 Myr) of the Paleogene, Hoploscaphites is the most widely and reliably recorded, with finds in Denmark, the Netherlands and the United States, and a possible record in Turkmenistan.^{[2][3][4][5][6]}

Species

A number of species have been described in the genus:

• H. angmartussutensis Birkelund, 1965
• H. birkelundae Landman & Waage, 1993
• H. crassus (Coryell & Salmon), 1934
• H. comprimus (Owen, 1852)
• H. constrictus (Sowerby, 1817)
• H. criptonodosus Riccardi, (1983)
• H. indicus (Forbes, 1846)
• H. landesi Riccardi, 1983
• H. melloi Landman & Waage, 1993
• H. nicolletii (Morton, 1842)
• H. pumilis Stephenson, 1941
• H. quiriquinensis Wilckens, 1904
• H. tenuistriatus (Kner, 1848)
• H. vistulensis Blaszkiewicz, 1980
• H. youngi Larson, 2016

References

• Paleontology portal

1. Hoploscaphites at Fossilworks.org
2. Landman, Neil H.; Goolaerts, Stijn; Jagt, John W.M.; Jagt-Yazykova, Elena A.; Machalski, Marcin (2015), Klug, Christian; Korn, Dieter; De Baets, Kenneth; Kruta, Isabelle (eds.), "Ammonites on the Brink of Extinction: Diversity, Abundance, and Ecology of the Order Ammonoidea at the Cretaceous/Paleogene (K/Pg) Boundary", Ammonoid Paleobiology: From macroevolution to paleogeography, vol. 44, Dordrecht: Springer Netherlands, pp. 497–553, doi:10.1007/978-94-017-9633-0_19, ISBN 978-94-017-9632-3, retrieved 2021-10-27
3. Machalski, Marcin; Heinberg, Claus (2005-12-31). "Evidence for ammonite survival into the Danian (Paleogene) from the Cerithium Limestone at Stevns Klint, Denmark". Bulletin of the Geological Society of Denmark. 52: 97–111. doi:10.37570/bgsd-2005-52-08. ISSN 2245-7070.
4. W. M. Jagt, John (2012-01-01). "Ammonieten uit het Laat-Krijt en Vroeg-Paleogeen van Limburg". Grondboor & Hamer. 66 (1): 154–183.
5. Landman, Neil H.; Garb, Matthew P.; Rovelli, Remy; Ebel, Denton S.; Edwards, Lucy E. (December 2012). "Short-Term Survival of Ammonites in New Jersey After the End-Cretaceous Bolide Impact". Acta Palaeontologica Polonica. 57 (4): 703–715. doi:10.4202/app.2011.0068. ISSN 0567-7920.
6. Machalski, Marcin; Jagt, John W.M.; Alekseev, Alexander S.; Jagt-Yazykova, Elena A. (December 2012). "Terminal Maastrichtian Ammonites from Turkmenistan, Central Asia". Acta Palaeontologica Polonica. 57 (4): 729–735. doi:10.4202/app.2011.0110. ISSN 0567-7920.

Further reading

• Arkell, W.J.; Kummel, B.; Wright, C.W. (1957). Mesozoic Ammonoidea. Treatise on Invertebrate Paleontology, Part L, Mollusca 4. Lawrence, Kansas: Geological Society of America and University of Kansas Press.
• Cobban, W.A. 1974. Ammonites from the Navesink Formation at Atlantic Highlands, New Jersey; USGS Prof Paper 845