To install click the Add extension button. That's it.

The source code for the WIKI 2 extension is being checked by specialists of the Mozilla Foundation, Google, and Apple. You could also do it yourself at any point in time.

4,5
Kelly Slayton
Congratulations on this excellent venture… what a great idea!
Alexander Grigorievskiy
I use WIKI 2 every day and almost forgot how the original Wikipedia looks like.
Live Statistics
English Articles
Improved in 24 Hours
Added in 24 Hours
What we do. Every page goes through several hundred of perfecting techniques; in live mode. Quite the same Wikipedia. Just better.
.
Leo
Newton
Brights
Milds

From Wikipedia, the free encyclopedia

Cidaridae
Temporal range: Lower Permian–Recent
Cidaris cidaris
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Echinodermata
Class: Echinoidea
Order: Cidaroida
Superfamily: Cidaroidea
Family: Cidaridae
Gray, 1825
Genera

See text

Cidaridae is a family of sea urchins in the order Cidaroida.

Description and characteristics

Typical test of a cidarid sea urchin (Phyllacanthus imperialis).

Cidarid sea urchins are characterized by their stout skeleton : the test is thick and hard, with massive perforated tubercles (never crenulated) surrounded by a crown of secondary tubercles, but no primary tubercles in the interambulacra regions. These tubercles hold massive spines, thick, strong and often very long, and showing sometimes odd shapes (thorny spines, fans, clubs, Christmas trees[1]...)[2] · .[3]

The order Cidaroida is the basalmost of current sea urchins, and most of the species included in this family are abyssal, even if a handful of species remain quite common in tropical shallow waters, like Eucidaris or Phyllacanthus.

Genera

Primary spines from the family Cidaridae

According to the World Register of Marine Species (WoRMS), the following genera are included in this family [4]

  • Subfamily Cidarinae (Mortensen, 1928a)
    • Genus Calocidaris (H.L. Clark, 1907)
    • Genus Centrocidaris (A. Agassiz, 1904)
    • Genus Chondrocidaris (A. Agassiz, 1863)
    • Genus Chorocidaris (Ikeda, 1941)
    • Genus Cidaris (Leske, 1778)
    • Genus Compsocidaris (Ikeda, 1939)
    • Genus Eucidaris (Pomel, 1883)
    • Genus Hesperocidaris (Mortensen, 1928b)
    • Genus Kionocidaris (Mortensen, 1932)
    • Genus Lissocidaris (Mortensen, 1939)
    • Genus Tretocidaris (Mortensen, 1903b)
  • Subfamily Goniocidarinae (Mortensen, 1928a)
    • Genus Austrocidaris (H.L. Clark, 1907)
    • Genus Goniocidaris (Desor, in Agassiz & Desor, 1846)
    • Genus Ogmocidaris (Mortensen, 1921)
    • Genus Psilocidaris (Mortensen, 1927)
    • Genus Rhopalocidaris (Mortensen, 1927)
    • Genus Schizocidaris (Mortensen, 1903b)
    • Genus Adelcidaris (Cotton & Godfrey, 1942) (nomen dubium)
  • Tribe Phyllacanthina (Smith & Wright, 1989)
  • Subfamily Stereocidarinae (Lambert, 1900)
    • Genus Phalacrocidaris (Lambert, 1902)
    • Genus Stereocidaris (Pomel, 1883)
  • Subfamily Stylocidarinae (Mortensen, 1903)

A now abandoned genus, Cidarites was used in the late 18th and early 19th century to describe a number of species of both cidarid and echid sea urchins.[5]

References

  1. ^ Mah, Christopher L. (December 7, 2009). "The Echinoderm Christmas Tree?? Antarctic Cidaroid Sea Urchins!". Echinoblog.
  2. ^ Mah, Christopher L. (August 20, 2013). "Strange Urchin Spines! Past and Present!". Echinoblog.
  3. ^ Mah, Christopher L. (May 20, 2015). "What is Going on with cidaroid sea urchins and their WEIRD spines??". Echinoblog.
  4. ^ WoRMS : Cidaridae
  5. ^ "Cidarites auct". WoRMS. Retrieved 9 April 2013.
This page was last edited on 4 December 2023, at 03:09
Basis of this page is in Wikipedia. Text is available under the CC BY-SA 3.0 Unported License. Non-text media are available under their specified licenses. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc. WIKI 2 is an independent company and has no affiliation with Wikimedia Foundation.