A Brief History of Crinoids

 

Commonly known as sea lilies, Crinoids are ‘flower-like’ organisms. As weird as it may sound, Crinoids look like flowers but are actually animals. Echinoderms and related to sea urchins, brittle stars, etc., and like other phylum members, Crinoids are spinny skinned and possess pentaradical symmetry. Having an endoskeleton of calcium carbonate, Crinoid fossils for sale might easily be available at a budget price if you look around since their skeletal remains are found in abundance and deemed extremely important. 

Crinoids were known for their carbonate-producing attribute throughout the Mesozoic and Paleozoic ages. In addition to this, the carbonate shelves of the Paleozoic and Mesozoic ages were made up of the remains of Crinoid and are another reason for the high demand for Crinoid fossils for sale. 

Structurally, Crinoids are described as starfish that have been turned upside down and have roots. A Crinoid's stem stretches down from what would be the top of a starfish, leaving the organism's mouth open skyward and its arms splayed out. Crinoid arms, on the other hand, appear articulated and feathery. The stalk stretches down from the calyx's aboral surface. Holdfasts on the stalk column secure the animal to the substrate.

The 'lily-like' appearance of the Crinoid is due to the three sections of the organism. What are these three sections? Well, the first section is the stem, then the calyx, and the third section is the arms of the Crinoid that filtered food from the surrounding. While Crinoids were generally known to live by attaching themselves to substrates, some of the fossils depicted their free-swimming states as well. 

As for their existence, the basic differentiation of the Crinoids was based on certain distinct characters such as the total plate circlets in the calyx, the position and presence or absence of other plates, the flexibility or rigidity of their attachment, etc. While the Paleozoic age saw the advent and existence of four different types of Crinoidea, namely, Disparida, Camerata, Flexibilia, and Cladida, a fifth kind- the Articiulata- was found in the post-Paleozoic era.

Due to their distinct attributes and the types that they existed in, Crinoid fossils for sale are in huge demand even today.