80431
As well as the aperture , some gastropod shells have additional openings in their shells for respiration ; this is the case in some Fissurellidae ( keyhole limpets ) where the central smaller opening at the apex of the shell is called an orifice , and in the Haliotidae ( abalones ) where the row of respiratory openings in the shell are also called orifices .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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