amphicoelous vertebra

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June 18, 2026

Quick Summary

An amphicoelous vertebra is characterized by being biconcave, meaning both the anterior and posterior surfaces of its centrum are concave. This term is derived from Greek, signifying "doubly hollow".1

While the term "amphicoelous" describes a specific vertebral shape, it is also used in taxonomy. For instance, Amphicoelia is an order of extinct crocodilians from the Mesozoic era that possessed amphicoelous or amphiplatyan presacral vertebrae.2

The vertebral column, a key component of the vertebrate skeleton, evolved from the notochord. A vertebra itself consists of a centrum and a neural arch that encloses the spinal cord. The amphicoelous shape is a specific variation within this structure.3

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Caudata
Bones and cartilage
…vertebrae are said to be amphicoelous (biconcave, or depressed on both the anterior and posterior sides), but, if it mineralizes or ossifies, the vertebrae are termed opisthocoelous (bulged on the anterior side and depressed on the posterior side). There is one cervical vertebra with a characteristic projection called the odontoid…
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…vertebrae are said to be amphicoelous (biconcave, or depressed on both the anterior and posterior sides), but, if it mineralizes or ossifies, the vertebrae are termed opisthocoelous (bulged on the anterior side and depressed on the posterior side). There is one cervical vertebra with a characteristic projection called the odontoid…
Read More