4" buying Edrioasteroids Echinoderm Fossil Mortality Plate Ordovician Age Kataoua Morocco Free Shipping

Location: Kataoua Formation, Blekus Morocco

Weight: 5.4 Ounces

Dimension: 4 Inches Long, 2.3 Inches Wide, 0.8 Inches Thick (Plate)

The item pictured is the one you will receive.

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Edrioasteroids are an extinct class of echinoderms. Distantly related to starfish and sea urchins, they have a body laid out in a pentaradial pattern. They also had a water vascular system and a skeleton made of calcite plates. They were filter feeders who lived permanently attached to an object or the seafloor. Some are thought to have had short stems like crinoids but most lived flat on whatever object they had attached to as larva. Edrioasteroids appear in the Cambrian Period about 515 million years ago. The zenith of their diversity during the Late Ordovician Period. By about 275 million years ago, during the Permian Period, Edrioasteroids are extinct.

Edrioasteroids were small organisms from a few millimeters to a couple of centimeters wide. They look like a tiny cushion attached to a substrate. The mouth was in the center of the theca (body) and from it, five ridges radiate out in a pentaradial pattern. These ambulacra channel food along the body to the mouth. There is little fossil evidence of how this was done, but by looking at modern echinoderms, it is likely Edrioasteroids had cilia or tube feet along the ambulacra that moved the food to the mouth. The ambulacra radiate out from the mouth in either straight lines or curves to form a whorl. Usually, they all curve in the same direction but in a few species the curve in different directions.

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Please be aware of the nature of fossils:

Being buried under the ground for millions of years under tons of pressure tends to be rough. No fossil comes out of the ground whole and perfect. Most fossils have undergone some restoration, while others are altered by man simply to enhance their presentation in different ways. The workers in Morocco do a very professional job, unearthing and preserving these natural treasures. These are part of the natural beauty of the fossil and not considered defects.

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