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.
D. biwae, after Yang and Shen, 2005 Difflugia biwae Kawamura, 1918 Diagnosis: Shell in lateral view fusiform in outline with a straight neck, a conspicuous
D. mulanensis, after Yang et al., 2015 Difflugia mulanensis Yang, Meisterfeld, Zhang and Shen, 2015 Diagnosis: Shell elongate ovoid like a vase, with a distinct
Euglypha bryophila, after Brown, 1911 (L), from Ecuador (R) Euglypha bryophila Brown, 1911 Diagnosis: (Original description) The test is very regular in form and subject
(A) A Scenedesmus cell (arrow) is engulfed by a trophozoite. (B) Several Scenedesmus cells adhere to the surface of a plasmodium that has numerous vacuoles
Actinosphaeridium spec. Diagnosis: Cell surrounded by a membranous shell, with an outer mucous layer. Filopodia with granules, sometimes branching. Cell stalked. Ecology: I found this
Euglyphidion enigmaticum – after Bonnet, 1960 Genus Euglyphidion Bonnet, 196 Diagnosis: Shell hyaline, ovoid, pseudostome circular or slightly elliptical. Shell loosely covered with two types of
Leptomyxa sp., slowly retracting in response to the light of the microscope Leptomyxa sp. Diagnose: This is a very large amoeba which I found in
Zivkovicia spec., 200 µm long; the right image is viewed through the aperture Zivkovicia spec. Diagnosis: Shell pyriform, circular in oral view, with a clear
P. pentangulostoma, after Quin et al., 2008 Pontigulasia pentangulostoma Quin et al., 2008 Diagnosis: Shell is brown, laterally uncompressed, parted to neck and body regions
Flabellula citata, from Dykova et al., 2008 Flabellula citata Schaeffer, 1926 Diagnosis: Length in locomotion 15-75 µm; width 25-55 µm. Shape very variable, from a