''Craspedites'' is an ammonoid cephalopod included in the

Perisphinctoidea Perisphinctoidea, formerly Perisphinctaceae, is a superfamily of Middle Jurassic (Bajocian) to Lower Cretaceous (Barremian) ammonites, commonly with evolute shells with strong ribbing that typically divides about mid flank before crossing the ven ...

that lived during the Late

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...

and Early

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

, found in

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

Greenland Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland is t ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populous ...

, and the

Russian Federation Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

Diagnosis and range

''Craspedites'', described by Aleksei Petrovich Pavlow in 1892, is characterized by a small, up to about 5 cm in diameter, smooth, essentially involute shell with simple ammonitic sutures. Whorl section is rounded, venter smooth; umbilicus small, exposing the dorsal portion of the inner whorls. Main sutural elements, primary saddles and lobes, are modified by small secondaries. ''Craspedites'' was thought to be restricted to the Upper Jurassic

Tithonian In the geological timescale, the Tithonian is the latest age of the Late Jurassic Epoch and the uppermost stage of the Upper Jurassic Series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma (million years ago). It is preceded by the K ...

until discovery of a new species, ''C. sachsi'', described from the

Berriasian In the geological timescale, the Berriasian is an age/stage of the Early/Lower Cretaceous. It is the oldest subdivision in the entire Cretaceous. It has been taken to span the time between 145.0 ± 4.0 Ma and 139.8 ± 3.0 Ma (million years ago) ...

age of

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

by A. E. Igolnikov in 2012, named in honour of

paleontologist Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...

V.N. Sachs.

Species

*''C. canadensis'' Jeletzky, 1966 *''C. ivanovi'' Gerasimov, *''C. jugensis'' Prigorovsky, 1906 *''C. kaschpuricus'' *''C. mosquensis'' Gerasimov, 1960 *''C. nodiger'' Eichwald, 1868 *''C. planus'' *''C. praeokensis'' Rogov, 2017 *''C. pseudofragilis'' Gerasimov, 1960 *''C. sachsi'' Igolnikov, 2012 *''C. shulginae'' Alifirov, 2009 *''C. singularis'' *''C. taimyrensis'' *''C. transitionis'' Rogov, 2017 *''C. unshensis''

References

* * Cretaceous ammonites Fossils of Poland Berriasian life Perisphinctoidea Ammonitida genera {{ammonitina-stub