Microworld

world of amoeboid organisms

Menu

 

Before a new shell is made, the amoeba collects building material in its environment. In this case Difflugia lobostoma uses small mineral grains, in other words: minute sand grains.
Amoebae can also use diatom shells or fragments, and mix it with mineral grains. Some amoeba secrete their own building material, called idiosomes, like granules (Arcella), squared plates (e.g. Quadrulella) or circular ones (e.g. Trinema, Cyphoderia). Other species strip the plates from the shells of their prey. In Nebela-species one can often see where the plates are derived from.
When the new shell is build, the amoeba uses its own cytoplasm as a matrix for the new shell. It secretes an organic cement and the mineral grains are arranged all over the matrix, often in a very regular and symmetric way. The organic cement hardens and holds the embedded material together.
The formation of a new shell can be completed within half an hour! See here for another division.

The new shell (right) is completed; it has a lighter color. In this case the amoeba moved into the new shell…
…and the old one was abandoned. Usually the cytoplasm divides and one of the cells moves into the new shell.
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 »

Haplomyxa spec

Fig. 1: Main cell body of specimen A, partly hidden by debris Haplomyxa sp. Three specimens were observed in a Petri dish, along with two

Read More »

Diplophrys spec. 7

Diplophrys spec., with three tufts of filopodia Diplophrys spec. These cells are granular, never seen before. I found them in a sample from the Bert

Read More »

Psammonobiotus spec.

I found this specimen in a sample from the Oppad, near Hilversum, 2020. It is similar to Psammonobiotus linearis, but lacks a clear spine at

Read More »

Sphenoderia compressa

Sphenoderia compressa, after Badewitz, 2002 Sphenoderia compressa Badewitz, 2002 Diagnosis: Test ovoid, oval in cross section, hyaline, covered with relatively small, oval, rather irregularly arranged

Read More »

Tracheleuglypha elongata

T. elongata, A-C after Thomas and Gauthier-Lièvre, 1959; D after Van Oye, 1959 Tracheleuglypha elongata Van Oye, 1959 Diagnosis: Test similar to T. dentata, but

Read More »