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Echinocorys is an extinct genus of echinoids that lived from the Late Cretaceous to the Paleocene. The genus belongs to the Holasteridae family. Its remains have been found in Asia, Europe, and North America.

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Echinopsis is an extinct genus of sea urchins in the class Echinoidea.

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Hemicidaris is an extinct genus of echinoids that lived from the Middle Jurassic to the Early Cretaceous. Its remains have been found in Africa, Asia, and Europe.

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Hemipneustes is an extinct genus of sea urchins belonging to the family Holasteridae.

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Heteraster is an extinct genus of sea urchins belonging to the family Toxasteridae.

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Marsupites is an extinct genus of crinoids from the Cretaceous.

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Micraster is an extinct genus of echinoids from the Late Cretaceous to the early Eocene. Its remains have been found in Africa, Antarctica, Europe, and North America. Micraster was an infaunal echinoid living in a burrow below the sediment surface. The test is clearly bilateral and there is a deep anterior groove to take in water containing organic particles to the mouth. The tube feet keep a supply of nutrient-laden water moving into the burrow. The anus has a waste tube behind it.

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Pentasteria is an extinct genus of sea star that lived from the Early Jurassic to the Early Cretaceous. Its fossils have been found in Europe.

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Phymosoma is an extinct genus of echinoids that lived from the Cretaceous to the Eocene. Its remains have been found in Asia, Europe, and North America.

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Temnocidaris is an extinct genus of echinoids that lived from the Late Cretaceous to the Paleocene. Its remains have been found in Europe and North America.

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Tylocidaris is an extinct genus of echinoids that lived from the Early Cretaceous to the Eocene. Its remains have been found in Europe and North America.