Six Different Kinds of Slime Moulds

 
Which one doesn't belong on the list?

1. Myxogastrea
2. Dictyostelia
3. Protostelia
4. Buddenbrockia
5. Myxococcales
6. Labyrinthulea
7. Acrasea

Check out Catalogue of Organisms, The Diversity of Slime Moulds for the correct answer.

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