world of amoeboid organisms

Belonocystis marina
B. marina, three spine-scales, after Klimov and Zlatogursky, 2016

Belonocystis marina  Klimov et Zlatogursky, 2016

Diagnosis: Spherical cells 6-8 µm in diameter with eccentric nucleus about 3-5 µm and a spherical nucleolus. Contractile vacuole absent. Cytoplasm is filled with small granules, yellowish crystals and food vacuoles. Floating or moving along the substratum with fine locomotive pseudopodia. Tightly packed scales surround the cell, being attached to short outgrowths on the cell surface. Individual scales are racket-shaped in optical section, 9-16 µm in length. The bulbous base of the scale is empty and has a latticed wall, consisting of fibrils which are connected with similar fibrils forming a pointed spike. The basal part also bears three circular latticed structures – the “skirts” with a proximal one being less electron-dense and two distal ones being denser and bearing thickened rims. May form large multinucleate cells that show amoeboid movement.

Ecology: Marine; tolerates salinities from 10 to 60‰ in culture. Type locality: Salt marsh near island Matrenin, Chupa inlet, Kandalaksha Bay, the White Sea, Russia.

Remarks: Differs from the two other described species because the scale bases are oval in optical section, not pentagonal (B. tubistella) or triangular (B. quadrangularis), and because the scales lack struts supporting the spike, but have “skirts” around the scale bases (the latter two features visible by electron microscopy).

Recent posts

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 »

Difflugia biwae

D. biwae, after Yang and Shen, 2005 Difflugia biwae Kawamura, 1918 Diagnosis: Shell in lateral view fusiform in outline with a straight neck, a conspicuous

Read More »

Difflugia mulanensis

D. mulanensis, after Yang et al., 2015 Difflugia mulanensis Yang, Meisterfeld, Zhang and Shen, 2015 Diagnosis: Shell elongate ovoid like a vase, with a distinct

Read More »

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 »


(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 »