An interesting group of testate amoebae is the genus Difflugia. There have been described hundreds of species, but the question is: how many of them are true species? Most descriptions are inaccurate of just based on one single test. Probably this group consists of several genera. Only DNA sequencing can help here. One of my projects is to make a visual map of all known species. It’s one of the most difficult taxa to identify.
Centropyxis halophila
C. halophila, after Bonnet, 1959 Centropyxis halophila Bonnet, 1959 Diagnosis: Shell with ovoid sole, extended by a rather strongly covering visor and not clearly separated