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]

References

  1. ^ a b c Treatise on Invertebrate Paleontology Part L Mollusca 4, Ammonoidea
  2. ^ Paleobiology Database


Allikas: https://en.wikipedia.org/wiki/Ussuritid
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