Agoniatitida

Agoniatitida Temporal range: 409 – 384 Ma PreꞒ Ꞓ O S D C P T J K Pg N Late Pragian – Middle Givetian
An image showing the siphuncle (which could be agoniatitid), the tube which connects the current living shell to the previous ones.
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	†Ammonoidea
Order:	†Agoniatitida Ruzhencev, 1957
Suborders
Agoniatitina Anarcestina Auguritina Gephuroceratina Gephurocerina Pharciceratina Timanocerina

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.