Ask the Chatbot Games & Quizzes ProCon History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture Money Videos
crinoid
Table of Contents
Introduction References & Edit History Quick Facts & Related Topics
Images
feather star Silurian coral-stromatoporoid community
Quizzes
Sea otter (Enhydra lutris), also called great sea otter, rare, completely marine otter of the northern Pacific, usually found in kelp beds. Floats on back. Looks like sea otter laughing. saltwater otters
Animal Group Names
Lion (panthera leo)
Deadliest Animals Quiz
Mute swan with cygnet. (birds)
Match the Baby Animal to Its Mama Quiz
vulture. An adult bearded vulture at a raptor recovery center. The Gypaetus barbatus also known as the Lammergeier or Lammergeyer, is a bird of prey and considered an Old World vulture.
Animal Factoids
Discover
Close up of books. Stack of books, pile of books, literature, reading. Homepage 2010, arts and entertainment, history and society
12 Novels Considered the “Greatest Book Ever Written”
Thumbnail for flags that look alike quiz Russia, Slovenia, Iceland, Norway
Flags That Look Alike
Diverse elementary school children wearing school uniforms running outside of school. Boys girls
Pro and Con: School Uniforms
Baseball laying in the grass. Homepage blog 2010, arts and entertainment, history and society, sports and games athletics
10 Greatest Baseball Players of All Time
The Cheshire Cat is a fictional cat from Lewis Carroll's Alice's Adventures in Wonderland. (Alice in Wonderland)
11 Banned Books Through Time
Los Angeles Police Department wanted flyer on Elizabeth Short, aka the "Black Dahlia," who was brutally murdered in January 1947. The FBI supported the Los Angeles Police Department in the case, including by identifying Short through her fingerprints that
America’s 5 Most Notorious Cold Cases (Including One You May Have Thought Was Already Solved)
Leonardo da Vinci (1452-1519), Italian Renaissance painter from Florence. Engraving by Cosomo Colombini (d. 1812) after a Leonardo self portrait. Ca. 1500.
10 Famous Artworks by Leonardo da Vinci
feather star
feather star

crinoid

class of echinoderm
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Share
Share to social media
URL
https://www.britannica.com/animal/crinoid
Feedback
Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login).
Thank you for your feedback

Our editors will review what you’ve submitted and determine whether to revise the article.

External Websites
Also known as: Crinoidea
Written and fact-checked by
The Editors of Encyclopaedia Britannica
Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.
The Editors of Encyclopaedia Britannica
Last Updated: • Article History

crinoid, any marine invertebrate of the class Crinoidea (phylum Echinodermata) usually possessing a somewhat cup-shaped body and five or more flexible and active arms. The arms, edged with feathery projections (pinnules), contain the reproductive organs and carry numerous tube feet with sensory functions. The tentacles have open grooves, along which cilia (minute, hairlike projections) sweep food particles toward the mouth.

The distinctive limy tests (internal skeletons of calcium carbonate) of crinoids make the thousands of extinct species (together with extinct echinoderms of similar form) important Paleozoic index fossils. About 700 living species are known, mainly from deep waters.

For more information about living crinoid species and groups, see feather star; sea lily.

Mute swan with cygnet. (birds)
Britannica Quiz
Match the Baby Animal to Its Mama Quiz
This article was most recently revised and updated by John P. Rafferty.