Microworld

world of amoeboid organisms

Menu
Mastigamoeba aspera, 110 µm

Mastigamoeba aspera Schulze, 1875

Diagnosis: Body semispherical or oval; during locomotion oval or pyriform; one motile cilium located at the anterior end of mononuclear forms; usually with a bulbous uroid; numerous conical or finger-shaped hyaline pseudopodia; outer surface usually inhabited by numerous rod-shaped ectobiotic bacteria; vesicular nucleus with a large central spherical nucleolus; cilium closely connected morphologically with the nucleus.

Dimensions: 50-250 long by about 50-100 µm broad, nucleus 16-20 µm, cilia c. 100 µm.

Ecology: in the ooze of ponds and ditches. It has also been found in brackish water (Carlos Gomez Revello, Uruguay, pers. comm., 2016)

Remarks: Both mononuclear cells with cilia and multinuclear cilium-free individuals have been observed. The base of the cilium is represented by a single kinetosome, from which radial microtubules and a lateral rootlet pass out into the cytoplasm. At the base of the kinetosome, there is a compact center of organization of microtubules (COMT), in which there are immersed bases of the nuclear cone microtubules participating in formation of karyomastigont. The structure of the cilium axoneme corresponds to the formula 9(2)+2. The main volume of the cytoplasm is occupied with digestive vacuoles. In addition, the cells contain numerous light-reflecting granules, as well as glycogen granules. Mitochondria, dictyosomes of the Golgi apparatus, and microbodies are not revealed (Chystyakova et al, 2012).

Mastigamoeba aspera
Mastigamoeba aspera, n = nucleus, f = cilium
Mastigamoeba aspera
Nucleus (n) and cilium (c)
Mastigamoeba aspera
Nucleus with supposed COMT (arrowed)
Mastigamoeba aspera
Mastigamoeba aspera
Dinamoeba mirabilis
Mastigamoeba aspera
Dinamoeba mirabilis
Mastigamoeba aspera, n=nucleus; note the numerous ectobiotic bacteria.
Dinamoeba mirabilis
Mastigamoeba aspera, F=cilium
Mastigamoeba aspera
Mastigamoeba aspera, arrows indicate bacteria – Micrograph Eckhard Voelcker
Dinamoeba mirabilis
Dinamoeba mirabilis
Mastigamoeba aspera, 94 µm – Den Treek, Amersfoort
Dinamoeba mirabilis
Mastigamoeba aspera, 94 µm – Den Treek, Amersfoort
Dinamoeba mirabilis
Mastigamoeba aspera, 94 µm – Den Treek, Amersfoort
Mastigamoeba aspera
Mastigamoeba aspera, 76 µm
Recent posts

Euglypha bryophila

Euglypha bryophila, after Brown, 1911 (L), from Ecuador (R) Euglypha bryophila  Brown, 1911 Diagnosis: (Original description) The test is very regular in form and subject

Read More »

Vernalophrys

(A) A Scenedesmus cell (arrow) is engulfed by a trophozoite. (B) Several Scenedesmus cells adhere to the surface of a plasmodium that has numerous vacuoles

Read More »

Actinosphaeridium spec.

Actinosphaeridium spec. Diagnosis: Cell surrounded by a membranous shell, with an outer mucous layer. Filopodia with granules, sometimes branching. Cell stalked. Ecology: I found this

Read More »

Euglyphidion

Euglyphidion enigmaticum – after Bonnet, 1960 Genus Euglyphidion Bonnet, 196 Diagnosis: Shell hyaline, ovoid, pseudostome circular or slightly elliptical. Shell loosely covered with two types of

Read More »

Leptomyxa spec.

Leptomyxa sp., slowly retracting in response to the light of the microscope Leptomyxa sp. Diagnose: This is a very large amoeba which I found in

Read More »

Zivkovicia spec.

Zivkovicia spec., 200 µm long; the right image is viewed through the aperture Zivkovicia spec.  Diagnosis: Shell pyriform, circular in oral view, with a clear

Read More »