This amazing photo by Rodolphe Holler was captured in the waters of New Caledonia and featured as NatGeo’s ‘Photo Of the Day’. Read Holler’s story here.

Crinoids are marine echinoderms (phylum Echinodermata). Crinoidea comes from the Greek word krinon, “a lily”, and eidos, “form”. ‘Sea lily’ refers to a crinoid which, in its adult form, is attached to the sea bottom by a stalk. Feather stars or comatulids refers to stalkless forms. They live both in shallow water and in depths as great as 6,000 meters.

Crinoids are characterized by a mouth on the top surface that is surrounded by feeding arms. They have a U-shaped gut, and their anus is located next to the mouth. Although the basic echinoderm pattern of fivefold symmetry can be recognized, most crinoids have many more than five arms. Crinoids usually have a stem used to attach themselves to a substrate, but many live attached only as juveniles and become free-swimming as adults.

There are only about 600 extant crinoid species, but they were much more abundant and diverse in the past. Some thick limestone beds dating to the mid- to late-Paleozoic are almost entirely made up of disarticulated crinoid fragments! Learn more.

Source: NatGeo Wikipedia

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