Diplophrys archeri Barker, 1868
Most likely ID: n.a.
Synonym: n.a.
Sampling location: Simmelried
Phylogenetic tree: Diplophrys archeri
Diagnosis:
- cells spherical or elliptical, with thin membrane
- two pseudostomes at opposite poles without neck
- diameter 8–20 µm
- pseudopodia straight or dichotomously branched
- several, peripher contractile vacuoles
- spherical nucleus with a central nucleolus
- one or several large oily droplets in cytoplasm
- oily droplet colorless, yellowish, orange or red
- can form colonies after several cell divisions
I find Diplophrys archeri frequently and regularly in the Simmelried. Especially in old samples with little plant material, the specimens can be found at the bottom of the container.
In my population almost all specimens had only an oil droplet of orange color. Only rarely was the oil colorless. The pseudopodia are often completely retracted under the coverslip. Therefore, the specimens should be placed under the coverslip with a high layer thickness and then allow to evaporate slowly. In rare cases Diplophrys archeri settles also on the floating coverslip.
The cells are surrounded by a thin, colorless membrane, which forms a soft test. This membrane is difficult to see, but in some specimens it is thicker (about 1.0–1.2 µm) and then easier to recognize (s. fig. 2).
Only very rarely do I find colonies of small specimens with a diameter of about 3–5 µm (s. fig. 3 a-b). These colonies develop when the mother cell divides rapidly several times in succession. The daughter cells formed then remain in the colony for some time.
Fig. 1: Diplophrys archeri. D = 17.9 µm. A specimen with widely spreaded, branched pseudopodia. Nu = nucleus. Obj. 100 X.
Fig. 2: Diplophrys archeri. D = 15.6 µm. A second specimen with spreaded pseudopodia. Note the hyaline membrane (HM) covering the cell. Obj. 60 X.
Fig. 3 a-b: Diplophrys archeri. A colony of about 20 cells. These colonies with small cells develop after rapid, multiple division of the mother cell. Obj. 60 X.