Testate amoebae with agglutinate shells: (A-D) shells composed of foreign material from the environment (xenosomes); (A, B) Difflugia oblonga; (C, D) Pontigulasia rhumbleri; (E-H) shells composed of siliceous shell-plates with different shape and size, obtained by predation mainly on small euglyphids; (E, F) Gibbocarina galeata; (G, H) Heleopera sylvatica.