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.Treatise on Invertebrate Paleontology Part L Mollusca 4, Ammonoidea
The Ussuritidae are most likely derived from the Dieneroceratidae and give rise to the Discophyllitidae. Seven genera are included: Ussurites Palaeophyllites Monophyllites Majsvarites Leiophyllites Eopsiloceras Eophyllites Genera are distinguished on the basis of shell morphology and characteristics of the suture.
Ussuritidae are also known as the Monophyllitidae, a junior synonym. Palaeophyllitidae, for Palaeophyllites, is sometimes found in the literature.
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