The Stalked Crinoids

Five hundred million years and three complete extinction’s of animals on the face of the earth, the stalked crinoid has re evolved time and time again. Fossil records have shown that this creature dates back to the late Cambrian period some 550 million years ago. A time when creatures crawled out of the ocean onto land. In 1864 a naturalist from Norway dredged up a “sea lily, a name given to the stalked crinoid fossils because of it lily like appearance. But it was not till 1972 that the two man sub Nekton Gamma observed them in their natural habitat for the first time. And it did not appear like a lily at all but like a walking tree.

Living Fossils

Their head or “crown” is made of many arms that contain pinules that catch plankton on a sticky mucus, then it is conveyed to the mouth via tiny hair like projections. Some of the pinules do not have this ability but contain reproductive cells.

Stalked crinoids usually have a holdfast adaptation with rootlike extension. They break from their anchoring hooks and crawl with their mouth up using their arms and dragging their stalk. Movement is accomplished via a water vascular system. The crinoids seek an area on haystack that is accessible to currents and plankton.

Witness this Incredible Event!

During a one year period and almost 1000 dives I observed a group of four crinoids at 800 feet. Mostly appearing sessile. It was in April 1998 that for a 2 week period I documented what appeared to be a mating between two crinoids. Day one, a stalked crinoid flares to give the appearance of a sea lily! Day two, the same crinoid breaks from its anchor and leaves the lower part of its stalk. It crawls to a point on the haystack some two feet away and below a taller staked crinoid. Day three, a larger crinoid bends down and makes contact crown to crown with the crawling crinoid. Day five, the crawling crinoid stands in close proximity to the now new mate. Day nine, the crawling crinoid now returns to the exact location it had begun.Day fourteen, except for the crawling crinoids shorted stature, all appears as it did two weeks prior.

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