microfaunas

/ˌmaɪkroʊˈfɔːnəz/
noun
  1. Plural of microfauna; very small animals (such as protozoa, nematodes, or tiny arthropods) that live in soil, water, or other environments.
    • The lake's microfaunas include rotifers and tiny crustaceans.
    • Different microfaunas thrive in sandy versus clay soils.
    • Researchers compared the microfaunas of two different compost piles.