Ussuritidae

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:

• Ussurites
• Palaeophyllites
• Monophyllites
• Majsvarites
• Leiophyllites
• Eopsiloceras
• Eophyllites

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]

References

1. ^ Treatise on Invertebrate Paleontology Part L Mollusca 4, Ammonoidea
2. ^ "Paleobiology Database". Archived from the original on 2007-10-01. Retrieved 2024-11-18.