Colleplax

Colleplax – a structure present in chileate brachiopods.

It is a triangular plate in the umbonal region of the ventral valve, covering an area that is otherwise externally exposed through the resorption of a part of the ventral valve.^[1] This aperture is supposed to have been covered by adhesive tissue,^[2] but no similar structure exists in any living brachiopod, so other interpretations have also been proposed.^[1]

References

^ ^a ^b Kaesler, Roger L. (1997). Treatise on Invertebrate Paleontology. Part H, Brachiopoda (revised), Volume 1. Boulder (Colo.): Geological society of America. pp. 359, 360, 427. ISBN 978-0-8137-3108-7.
^ "The external surface of Dictyonella and of other pitted brachiopods | The Palaeontological Association". www.palass.org. Retrieved 2023-07-20.

[:0-1] Kaesler, Roger L. (1997). Treatise on Invertebrate Paleontology. Part H, Brachiopoda (revised), Volume 1. Boulder (Colo.): Geological society of America. pp. 359, 360, 427. ISBN 978-0-8137-3108-7.

[2] "The external surface of Dictyonella and of other pitted brachiopods | The Palaeontological Association". www.palass.org. Retrieved 2023-07-20.

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