A paxilla (plural. paxillae) is a small umbrella-shaped structure sometimes found on Echinoderms, particularly in starfish (class Asteroidea) such as Luidia, Astropecten and Goniaster that immerse themselves in sediment. They are ossicles composed of calcite microcrystals found on the aboral (upper) surface of the animal. Their stalks emerge from the body wall and their umbrella-like crowns, each fringed with short spines, meet edge-to-edge forming a protective external false skin. The water-filled cavity beneath contains the madreporite and delicate gill structures known as papullae.[1]
References
^Ruppert, Edward E.; Fox, Richard, S.; Barnes, Robert D. (2004). Invertebrate Zoology, 7th edition. Cengage Learning. p. 877. ISBN81-315-0104-3.
This article about anatomy of the phylum Echinodermata is a stub. You can help Wikipedia by expanding it.
paxilla, ossicle, paxilla, plural, paxillae, small, umbrella, shaped, structure, sometimes, found, echinoderms, particularly, starfish, class, asteroidea, such, luidia, astropecten, goniaster, that, immerse, themselves, sediment, they, ossicles, composed, calc. A paxilla plural paxillae is a small umbrella shaped structure sometimes found on Echinoderms particularly in starfish class Asteroidea such as Luidia Astropecten and Goniaster that immerse themselves in sediment They are ossicles composed of calcite microcrystals found on the aboral upper surface of the animal Their stalks emerge from the body wall and their umbrella like crowns each fringed with short spines meet edge to edge forming a protective external false skin The water filled cavity beneath contains the madreporite and delicate gill structures known as papullae 1 References Edit Ruppert Edward E Fox Richard S Barnes Robert D 2004 Invertebrate Zoology 7th edition Cengage Learning p 877 ISBN 81 315 0104 3 This article about anatomy of the phylum Echinodermata is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Paxilla ossicle amp oldid 1048592532, wikipedia, wiki, book, books, library,
