Microworld

world of amoeboid organisms

Menu
Paramoeba spec. with one and two PLOs.

Family Paramoebidae Poche, 1913, emend. Kudryavtsev et al., 2011

Diagnosis: Flattened dactylopodial amoebae with blunt, hyaline subpseudopodia, conical or finger-shaped in outline. Floating form often with radiating pseudopodia. Uninucleate with central nucleolus.
Cell coat consists of microscales, dense amorphous glycocalyx that may include hair-like structures, or dome-shaped glycostyles with hexagonal bases.
One genus of this family, Paramoeba, contains a deeply-specialized kinetoplastid symbiont Perkinsela amoebae (Hollande, 1980) Dyková et al., 2008 (also called Perkinsela-like organism, PLO, formerly called parasome) located in the cytoplasm near the nucleus.
At the ultrastructural level, two features are of diagnostic importance:

  • Surface layer is complex and highly differentiated as a cuticle or as boat-shaped microscales discernable at the TEM level;
  • Pseudopodia are without a filamentous core (as in Vexilliferidae).

Key to genera:

1 Cell with PLO > Paramoeba

– Cell without PLO > Korotnevella

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 »

Lachmannia spec.

“Lachmannia” spec., body length 127 µm “Lachmannia” spec. I found two cells, size about 125 µm when ovoid, with an organic-walled membranous test and a

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 »