Ussuniidae is a monogeneric
family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
of
Ordovician
The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...
brachiopod
Brachiopods (), phylum (biology), phylum Brachiopoda, are a phylum of animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear e ...
s aligned with the
Trimerellids, but showing additional similarities to the
craniids and considered intermediate in
morphology
Morphology, from the Greek and meaning "study of shape", may refer to:
Disciplines
*Morphology (archaeology), study of the shapes or forms of artifacts
*Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...
.
References
{{Taxonbar, from=Q33137448
Craniata
Prehistoric brachiopods