These 10 groups are based on a survey conducted of the African species of Difflugia [3] The 10 shell shape classifications are lobed, collared, compressed, urceolate, globose, ovoid-globose, elongate, acute angled, horned and pyriform.

In addition, most initial descriptions of Difflugia speciation were completed using light microscopy and therefore lacked the technology to show the details of test structure and composition.

[5] The invention of scanning electron microscopy allows for more detail and improved the taxonomic work surrounding Difflugia.

[5] Molecular phylogenetic analyses have revealed that the genus Difflugia, as traditionally defined, is not a monophyletic group.

The environment conditions in which Difflugia lives is important to consider as it greatly influences shell morphology of the species.

Difflugia can be found living in a large variety of habitats such as freshwater sediments, dry mosses and soil, or lakes.

Some species are planktonic and switch to a benthic phase during the winter in which they stay immobile near the bottom of the body of water.

[9] Another problem arise from the distortion of test and changes to the xenosomes that makes genera difficult to identify from the testate amoebae fossil specimen alone.