Ussuritidae

Ussuritidae
Temporal range: Triassic
Fossil of Monophyllites sphaerophyllus from Bosnia, on display at Galerie de paléontologie et d'anatomie comparée in Paris
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Suborder: Phylloceratina
Family: Ussuritidae
Hyatt, 1900

Ussuritidae are ancestral, Triassic, Phylloceratina characterized by generally smooth, discoidal, evolute shells with rounded venters and little or no ornamentation and by sutures with primitive monophyllitic saddles with a single terminal branch or leaflet.[1]

The Ussuritidae are most likely derived from the Dieneroceratidae[1] and give rise to the Discophyllitidae. Seven genera are included:

Genera are distinguished on the basis of shell morphology and characteristics of the suture.[1]

Ussuritidae are also known as the Monophyllitidae, a junior synonym. Palaeophyllitidae, for Palaeophyllites, is sometimes found in the literature.[2]