Learn About Sea Pens & Relatives

There are several deep-water species of sea pens on our coast, but only one that lives commonly in shallow-water.

ANIMATION of snail meeting SEA PEN
© 2010 Thomas Carefoot

To learn about west-coast SEA PENS: select a topic from the Cnidaria > Sea pens menu at the top of the page

OR: play the ANIMATION of the snail meeting the SEA PEN

OR, if you want to see other animations: follow the snail on its ODYSSEY by CLICKING on any X-marked invertebrate on the map

Phylum Cnidaria (lit. “nettle-bearing” G.), referring to the nematocysts possessed by all members of the phylum; includes sea anemones, corals, sea pens, gorgonians, jellyfishes, hydroids

Class Anthozoa  (lit. “flower animal” G.), including sea anemones, sea pens, corals, and cup corals

Subclass Octocorallia (=Alcyonaria) (lit. “eight coral” G.), referring to 8 sets of mesenteries, and poyps bearing eight tentacles; includes mostly colonial animals such as soft corals, gorgonians, and sea pens

Order Pennatulacea (lit. “feather characterised by” L.), including sea pens and sea pansies

Order Alcyonacea (lit. “zoophyte” G.), including soft corals such as Alcyonium spp. and Cryptophyton goddardi

NOTE  the west-coast soft coral commonly known as Gersemia rubiformis is apparently an undescribed specis of Alcyonium.  Fautin & Hand 2007 p. 173 In, The Light and Smith manual. Intertidal invertebrates from central California to Oregon (Carlton, ed.) Univ Calif Press, Berkeley