Calyptra

Calyptra (from (kalúptra) "veil") is a scientific term used in botany. It describes a feature in plant morphology.

In bryophytes, the calyptra (plural calyptrae) is an enlarged archegonial venter that protects the capsule containing the embryonic sporophyte. The calyptra is usually lost before the spores are released from the capsule. The shape of the calyptra can be used for identification purposes.

In flowering plants, the calyptra is a covering tissue for stamens and carpels. The name is also used for the capping tissue of roots, the root cap.

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