Cidaroida
   HOME

TheInfoList



OR:

Cidaroida is an order of primitive
sea urchin Sea urchins () are spiny, globular echinoderms in the class Echinoidea. About 950 species of sea urchin live on the seabed of every ocean and inhabit every depth zone from the intertidal seashore down to . The spherical, hard shells (tests) of ...
s, the only living order of the subclass Perischoechinoidea. All other orders of this subclass, which were even more primitive than the living forms, became extinct during the
Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...
.


Description

Their primary spines are much more widely separated than in other sea urchins, and they have no buccal slits. Other primitive features include relatively simple plates in the
test Test(s), testing, or TEST may refer to: * Test (assessment), an educational assessment intended to measure the respondents' knowledge or other abilities Arts and entertainment * ''Test'' (2013 film), an American film * ''Test'' (2014 film), ...
, and the
ambulacral Ambulacral is a term typically used in the context of anatomical parts of the phylum Echinodermata or class Sea star, Asteroidea and Edrioasteroidea. Echinoderms can have ambulacral parts that include Ossicle (echinoderm), ossicles, plates, spines ...
plates continuing as a series across the membrane that surrounds the mouth.


Families

According to
World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive list of names of marine organisms. Content The content of the registry is edited and maintained by scientific specialist ...
: * family Anisocidaridae Vadet, 1999 † * super-family Cidaridea Gray, 1825 ** family
Cidaridae Cidaridae is a family of sea urchins in the order Cidaroida. Description and characteristics Cidarid sea urchins are characterized by their stout skeleton : the test is thick and hard, with massive perforated tubercles (never crenulated) sur ...
Gray, 1825 ** family Ctenocidaridae Mortensen, 1928a ** family Paurocidaridae Vadet, 1999a † * family Diplocidaridae Gregory, 1900 † * family Heterocidaridae Mortensen, 1934 † * super-family Histocidaroidea Lambert, 1900 ** family Histocidaridae Lambert, 1900 ** family
Psychocidaridae Psychocidaridae is a family of sea urchins in the order Cidaroida. The genus '' Psychocidaris'' is extant while the other genera are only known from fossils. The family has been in existence since the Lower Jurassic (Toarcian) and the range incl ...
Ikeda, 1936 * family Miocidaridae Durham & Melville, 1957 † * family Polycidaridae Vadet, 1988 † * family Rhabdocidaridae Lambert, 1900 † * family Serpianotiaridae Hagdorn, 1995 † * family Triadocidaridae Smith, 1994c Image:Stylocidaris affinis.jpg, '' Stylocidaris affinis'' (
Cidaridae Cidaridae is a family of sea urchins in the order Cidaroida. Description and characteristics Cidarid sea urchins are characterized by their stout skeleton : the test is thick and hard, with massive perforated tubercles (never crenulated) sur ...
) Image:Notocidaris.jpg, '' Notocidaris sp.'' ( Ctenocidaridae) Image:Histocidaris variabilis.jpg, '' Histocidaris variabilis'' ( Histocidaridae) Image:Tylocidaris ohshimai.JPG, '' Tylocidaris ohshimai'' (
Psychocidaridae Psychocidaridae is a family of sea urchins in the order Cidaroida. The genus '' Psychocidaris'' is extant while the other genera are only known from fossils. The family has been in existence since the Lower Jurassic (Toarcian) and the range incl ...
) Image:Miocidaris coaeva MHNT.PAL.2006.94.jpg, '' Miocidaris coaeva'' ( Miocidaridae, fossil) Image:Paracidaris florigemma.JPG, '' Paracidaris florigemma'' ( Polycidaridae, fossil)
Image:Cidaris blakei.jpg, '' Cidaris blakei'', abyssal Caribbean species Image:Eucidaris tribuloides (Slate-pencil Urchin).jpg, '' Eucidaris tribuloides'', shallow Caribbean species Image:Phyllacanthus.jpg, ''
Phyllacanthus imperialis ''Phyllacanthus imperialis'', also known as the Sputnik urchin, imperial lance urchin, imperial sea urchin, imperial urchin, pencil sea urchin, lance urchin, knobby sputnik sea urchin, mine urchin, and land mine sea urchin, is a species of sea u ...
'', shallow Indo-Pacific species Image:Plococidaris verticillata.jpg, '' Plococidaris verticillata'', rare shallow Indo-Pacific species Image:Prionocidaris baculosa.jpg, '' Prionocidaris baculosa'', from Philippines Image:Reef0228.jpg, '' Chondrocidaris gigantea'', from Hawaii


References


Citations


Sources

* * * Cisuralian first appearances Extant Permian first appearances {{echinoidea-stub