Echinoderms!

I love "how to tell these things apart"/"what are the differences" posts and Chrism of the Echinoblog has a fine post on how to tell asteroids and ophiuroids apart.

Choriaster granulatus, an example of my favorite type of starfish (CHUNKY)

Messersmith, J. (2009, March 31). Underwater variety pack [Web log message]. 

Retrieved from http://www.messersmith.name/wordpress/2009/03/31/underwater-variety-pack/ 

BRIEF EXPLANATION: Both asteroids and ophiuroids are echinoderms, the group that includes sea stars (starfish), sea urchins, sea cucumbers, sand dollars, crinoids and all those cool invertebrate cats.   HOWEVER, not all starfish are equal! What the general public calls "starfish" can be categorized as asteroids ("sea stars") or ophiuroids ("brittle stars").  I will let Chrism tell you the rest.  Enjoy and consider this an appetizer to a series I'm planning on doing about invertebrates, because people absolutely do not care enough about invertebrates.

Because people do not care enough, here is a link to Circus of the Spineless, a blog carnival starring some of the folks I regularly follow that is devoted to invertebrates both terrestrial and other.