371565
There are at least 956 nominal species of gastropods , which breaks down to about 250 species of freshwater gastropod s , and about 700 species of land gastropods ( 590 species of snail s and approximately 110 ( ? )
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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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