''Bostrychoceras'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of heteromorph

ammonite Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

from the family

Nostoceratidae Nostoceratidae is a diverse Family (biology), family of heteromorph ammonites found throughout the oceans of the world during the Late Cretaceous. The nostoceratids are famous for the bizarre coiling of their shells. Many genera, such as ''Yezo ...

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s have been found in

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

sediments in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

and

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

. The shell of ''Bostrychoceras'' begins as a tightly wound helical spire, like that of ''

Nostoceras ''Nostoceras'' is an extinct genus of ammonites. The etymology of the name ''Nostoceras'' comes from "nostos" meaning return and "ceros" meaning horn, named as such by Alpheus Hyatt because it bends back on itself. Taxonomy ''Nostoceras'' is th ...

'', from which hangs a U or J shaped body chamber, at least in the adult. The shell is covered with dense, strong, but un-flaired, ribs that are commonly sinuous and oblique. May nor may not have strong constrictions.

Distribution

Cretaceous of Nigeria, Peru, South Africa, Spain and the United States

References

;Notes ;Bibliography * * ''Ammonoid Paleobiology'' (Topics in Geobiology) by Neil H. Landman, Kazushige Tanabe, and Richard Arnold Davis Ammonitida genera Nostoceratidae Late Cretaceous ammonites of Europe Late Cretaceous ammonites of North America Campanian life {{ammonitida-stub