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:
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