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Spirifer striata

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A fossil brachiopod found in Carboniferous rocks from Ardclough, Ireland, about 330 million years old. Its true width is 10 cm, height 5 cm. Brachiopods are often confused with the two-shelled 'sea shell' animals called bivalves found on beaches today; however, they are a completely different group of animals. There are over 100 genera (groups of species) of brachiopod found in seas all around the world today and their fossil record goes back to the Cambrian, around 560 million years ago.

Their hard shell protects the soft parts of their body and is made up of two shells called 'valves', a dorsal and a ventral valve. This specimen has been prepared so that the dorsal valve has been removed revealing the inside of the fossil. When the brachiopod was alive the coiled spirals would have been covered in soft tissues and fine tentacles to form an organ called the lophophore which is used for feeding.

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