Wikipedia
Arkelloceras
Arkelloceras is an early Middle Jurassic ( Bajocian stage) Stephanoceratacean (Ammonitina) genus from arctic Canada, Alaska, and Siberia belonging to the family Otoitidae (Imlay 1984, Westermann 1965)
Arkelloceras seems to be a direct descendant of Abbasites and is thought to have given rise to Ermoceras and possibly to Thamboceras. (Westermann 1965)