Microworld

world of amoeboid organisms

Menu
Artodiscus saltans
Artodiscus saltans, river Saar, Germany

Artodiscus saltans Penard, 1890

Diagnosis: Shell a flexible membrane, spherical to polyhedral, covered with very small grains of various kinds; nucleus eccentric, finely granulated with a small nucleolus; 7-12 slowly moving projections, which look like filopodia or cilia, extend through pores of the envelope; base of these projections thickened. In normal locomotion the cell has one leading filopodium with two trailing filopodia behind, shaped like a Y. These three filopodia don’t hardly move; the other filopodia are moving like flagella, making rowing movements.

Dimensions: Penard 18-23 µm; De Groot (1979): 27-40 µm (n=4); my measurements: 13-24 µm (n=15).

Ecology: fresh and brackish water. In sediments of ditches, lakes and rivers, also reported from a flooded pasture (Penard, 1890) . Penard (1890), De Groot (1979) and Török (2006) have collected this species in clear running waters. I found it in following locations:

  • 1973 in the Spiegelplas, a large (280 ha) and deep (45 m) lake which has been dredged for sand supply in the sixties. The lake has very clear water and is only fed by rain and seepage. In 2013 I found this species again, after 40 years, at the same location.
  • 2012 in a shallow ditch along a forest in Gaasterland, Friesland, the Netherlands. Stagnant oligotrophic water.
  • 2014 one specimen in the river Saar in Germany, not exactly very clean and clear water!
  • 2015 one specimen in a sample from floating debris shortly after the ice in the ditches has melted. This sample came from an eutrophic ditch near the Naardermeer, the Netherlands.
  • 2015 some specimens in brackish water from an old washing basin along the French coast.
  • 2015 specimen in the IJsselmeer, a very large lake, near Kornwerderzand, where the water is shallow and oligotrophic.
  • 2017 specimens in the river Jonte in Southern France.

Remarks: Though the projections move slowly, the organism moves relatively fast in de direction of one leading projection. Because of the cilia-like movement of the projections, this species has been moved to the group of residual heterotrophic flagellates. Further investigations are needed to clear its taxonomic status. In its behavior and the presence of cilia-like filopodia with thickened base, this species closely resembles Paramphitrema species.
In a wet mount, kept for more than a week in a moist chamber, this species multiplied.

Reference: Ntakou, E., Siemensma, F., Bonkowski, M., Dumack, K., 2019. The Dancing Star: Reinvestigation of Artodiscus saltans (Variosea, Amoebozoa) Penard 1890. Protist, 170: 349-357.

Artodiscus saltans
Artodiscus saltans, cell c. 19.5 µm – Spiegelplas
Artodiscus saltans
Artodiscus saltans
Flexible test, covered with scales?
Artodiscus saltans
Artodiscus saltans
Reddish color in one specimen and (r) polyhedral shape
Artodiscus saltans
Artodiscus saltans
Filopodia or cilia?
Artodiscus saltans
Artodiscus saltans
Artodiscus saltans, 21 µm, the same specimen; the arrow indicates the basal thickening
Artodiscus saltans
Artodiscus saltans
Arrows indicate the basal thickening
Artodiscus saltans
From: Penard, in Faune Rhizopodique du Bassin de Léman, 1902
Artodiscus saltans
Artodiscus saltans
Artodiscus saltans
Artodiscus saltans
Artodiscus saltans
Artodiscus saltans, 24 µm
Artodiscus saltans
Artodiscus saltans, 24 µm
Recent posts

Zivkovicia compressoidea

Z. compressoidea, a-b after Chardez, 1958; c after Jung, 1942 Zivkovicia compressoidea  (Jung, 1942) new.comb. Basionym: Pontigulasia compressoidea Jung, 1942 Diagnosis: Shell ovoid and compressed,

Read More »

Zivkovicia flexa

Z. flexa, from Cash and Hopkinson, 1909 Zivkovicia flexa  (Cash and Hopkinson, 1909) Ogden, 1983 Basionym: Pontigulasia compressa var. flexa  Cash and Hopkinson, 1909 Diagnosis:

Read More »

Lagenodifflugia epiouxi

L. epiouxi, after Chardez, 1984 3 Lagenodifflugia epiouxi (Chardez, 1983) new comb. Basionym: Pontigulasia epiouxi Chardez, 1983 Diagnosis: Shell elongate, circular in cross-section or very

Read More »

Centropyxis lapponica

Centropyxis lapponica, after Grospietsch, 1954 Centropyxis lapponica  Grospietsch, 1954 Diagnosis: Shell nearly circular in circumference, without spines. Aperture clear square with rounded corners. Shell viewed

Read More »

Chaos spec. 6

Chaos spec., Crailoo, 2021 Chaos spec. This specimen was found in a samples from Crailoo, Netherlands. It was remarkable because of the absence of crystals.

Read More »

Bullinularia maxima

Bullinularia maxima – from Bobrov and Mazei, 2020 Bullinularia maxima Bobrov et Mazei, 2020 Diagnosis: Shell brown, opaque, elliptical in ventral view; ventral surface is

Read More »

Bullinularia macroporum

Bullinularia macroporum – from Bobrov and Mazei, 2020 Bullinularia macroporum Bobrov et Mazei, 2020 Diagnosis: Shell yellow-brownish, transparent, circular in ventral view; ventral surface is

Read More »

Nebela golemanskyi

N. golemanskyi, after Todorov, 2010 Nebela golemanskyi Todorov, 2010 Diagnosis: Shell large, colourless and pyriform, with a distinct short neck about one fourth of the

Read More »

Nebela nebeloides

N. nebeloides, after Gauthier-Lièvre and Thomas, 1958 Nebela nebeloides (Gauthier-Lièvre and Thomas, 1958) Todorov et al., 2010 Basionym: Difflugia nebeloides Gauthier-Lièvre and Thomas, 1958 Diagnosis:

Read More »