Microworld

world of amoeboid organisms

Menu

I have made the drawings below in 1977. I found these tests in sediment of peat bogs in het Hol, the Netherlands.

Allogromia spec.
This test contained a remarkable small cell which didn’t fill the test as usual. Both are tests of Lacogromia cassipara.
Allogromia spec.
Allogromia spec.
Two different tests, one small, (Allogromia nigricans?) the other broader and also much larger. The latter contained a living cell which had a large nucleus, in which I could not detect any structure. The cytoplasm was black-brown and contained small reddish peanut-shaped granules, the membrane of the test was grey.
Allogromia spec.
Two large empty tests, with distinct collars, which is typical for Lacogromia cassipara morphotype B.
Lacogromia cassipara

I found three shells of Lacogromia cassipara with a living cell inside. One individual contained c. 8 nuclei (left), the other two had only one nucleus. All nuclei were 40-42 µm in diameter.

Lacogromia cassipara
Four empty shells in the sediment of a peat bog. Note the difference in shape.
Lacogromia cassipara
Two living cells, one 268 µm long and the other 120 µm. Both cells had a distinct peduncle. The large cell contained c. 30 nuclei, each 12 µm in diameter, and the other cell 3 nuclei, size unknown.
Lacogromia cassipara
Lacogromia cassipara, with one nucleus and a distinct peduncle or Pseudopodienstiel, photographed 1983.
Recent posts

Penardochlamys arcelloides

P. arcelloides – after Penard, 1904 Penardochlamys arcelloides  (Penard, 1904) Deflandre, 1953 Diagnosis: Colorless or very slightly yellowish envelope, bag or cauldron-shaped, very thin, chitinous,

Read More »

Reticulomyxa hannae

R. hannae, plasmodium – photomicrograph Steffen Clauss Reticulomyxa hannae Völcker and Clauß, 2020 Diagnosis: Trophozoites surrounded by a very thin mucous envelope, with slowly moving plasmodia, variable

Read More »

Velamentofex saxonensis

V. saxonensis, feeding (photomicrograph Steffen Clauss) Velamentofex saxonensis Völcker and Clauß, 2020 Diagnosis: Trophozoites ovoid, 30-95 μm, granuloreticulopodia up to 1000 μm long. with a hyaline, thin

Read More »

Velamentofex tyrolensis

V. tyrolensis (photomicrograph Steffen Clauss) Velamentofex tyrolensis Völcker and Clauß, 2020 Diagnosis: Trophozoites ovoid, 98-125 μm, with reticulopodia up to 300 μm long, with a hyaline,

Read More »

Velamentofex berolinensis

V. berolinensis Velamentofex berolinensis Völcker and Clauß, 2020 Diagnosis: Trophozoites ovoid, 50-300 µm, with a hyaline, extremely flexible, membranous test. Nuclei numerous, 11.6-16.2 µm in diameter,

Read More »

Lieberkuehniidae

 Lieberkuehniidae  Siemensma, Holzmann, Apothéloz-Perret-Gentil, Clauß, Voelcker, Bettighofer, Khanipour Roshan, Walden, Dumack and Pawlowski, 2020 Diagnosis: Multinucleate organic-walled monothalamous foraminifera. Test very flexible, elongated to broadly

Read More »