Agoniatitida

Agoniatitida, also known as the Anarcestida, is the ancestral order within the cephalopod subclass Ammonoidea originating from bactritoid nautiloids, that lived in what would become Africa, Asia, Australia, Europe, and North America during the Devonian from about the lower boundary of Zlichovian stage (corresponding to late Pragian, after 409.1 mya) into Taghanic event during upper middle Givetian (between 385 and 384 mya), existing for approximately 25 million years.