Cidaroida

Cidaroida Temporal range: Lower Permian–Recent PreЄ Є O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Echinodermata
Class:	Echinoidea
Subclass:	Perischoechinoidea
Order:	Cidaroida Claus, 1880
Families
Cidaridae Psychocidaridae

Cidaroida is an order of primitive sea urchins, the only living order of the subclass Perischoechinoidea. All other orders of this subclass became extinct during the Mesozoic, and were even more primitive than the living forms.

Their primary spines are much more widely separated than in other sea urchins, and they have no gills. Other primitive features include relatively simple plates in the test, and the ambulacral plates continuing as a series across the membrane that surrounds the mouth.

References

• Barnes, Robert D. (1982). Invertebrate Zoology. Philadelphia, PA: Holt-Saunders International. p. 980. ISBN 0-03-056747-5. 
• National History Museum. "Cidaroida". http://www.nhm.ac.uk/research-curation/research/projects/echinoid-directory/taxa/taxon.jsp?id=1857. Retrieved 20th Dec 2009. 

This echinoderm-related article is a stub. You can help Wikipedia by expanding it.v · Categories: Echinoidea Echinoderm stubs Wikimedia Foundation. 2010. Игры ⚽ Нужно решить контрольную? Cidaris List of Don Quixote characters Look at other dictionaries: Cidaroida — Cidaroida …   Wikipédia en Français cidaroida — cid·a·roi·da …   English syllables cidaroida — ˌsidəˈrȯidə noun plural Usage: capitalized Etymology: New Latin, from Cidaris + oida : the oldest surviving order of sea urchins containing the most primitive of living forms, all lacking peristomial gills and sphaeridia but having an apically… …   Useful english dictionary Sea urchin — Taxobox name = Sea urchin image width = 250px image caption = Sea urchins, Sterechinus neumayeri regnum = Animalia phylum = Echinodermata subphylum = Echinozoa classis = Echinoidea classis authority=Leske, 1778 subdivision ranks = Subclasses… …   Wikipedia Perischoechinoidea — rezenter Lanzenseeigel Zeitraum Ordovizium bis heute 449 bis 0 Mio. Jahre Systematik …   Deutsch Wikipedia Echinodermata (classification phylogénétique) — Cette page a pour objet de présenter un arbre phylogénétique des Echinodermata (Échinodermes), c est à dire un cladogramme mettant en lumière les relations de parenté existant entre leurs différents groupes (ou taxa), telles que les dernières… …   Wikipédia en Français Echinoidea — Pour les articles homonymes, voir oursin. Oursin …   Wikipédia en Français Cidaridae — Temporal range: Lower Permian–Recent …   Wikipedia Cidaridae — Cidaridea Sty …   Wikipédia en Français Perischoechinoidea — Prionocidaris hawaiiensis …   Wikipédia en Français 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”