Where did they live? Crinoids are saltwater animals and most live attached to the sea floor by their stalks. A few modern species have lost the stalk and can swim by moving their arms.

What time period did crinoids live in?

Crinoids are marine animals belonging to the phylum Echinodermata and the class Crinoidea. They are an ancient fossil group that first appeared in the seas of the mid Cambrian, about 300 million years before dinosaurs. They flourished in the Palaeozoic and Mesozoic eras and some survive to the present day.

Where are crinoids found?

Well-preserved specimens are found in the limestone cliffs along the Mississippi River between Burlington and Alton. The oldest crinoids come from Ordovician rocks. Some crinoids live today, mainly in deep parts of the ocean, but they are not nearly as common as in the past.