world of amoeboid organisms


Centropyxis halophila

C. halophila, after Bonnet, 1959

Centropyxis halophila Bonnet, 1959

Diagnosis: Shell with ovoid sole, extended by a rather strongly covering visor and not clearly separated from the sole. In ventral view, elliptical to oblong in outline, without restriction at the origin of the visor. Crescent-shaped pseudostome, always visible in ventral view. In lateral view, the axis of symmetry of the sole forms an angle of approximately 40° with the plane determined by the edge of the pseudostome. Aperture of the belly large enough, not a diaphragm. Shell wall made up of amorphous siliceous particles of fairly large dimensions and separated by an abundant yellowish cement, exuding at the bonds and incorporating very small mineral elements. Cyst yellowish, 30-35 µm in diameter.

Dimensions: Total length 65 to 75 um; long axis of the sole 50 to 55 µm; minor axis 45-50 µm; visor height 15-20 µm.

Ecology: Salt marshes, Europe.
Bonnet (1959) found this species remarkably consistent along the coast of the Languedoc and Roussillon (France). He found it in abundance in the substrate of Salicornietum fruticosae, in a grayish soil, composed of 25% fine sand and 75% silt, attached to a carbonate gley. Its NaCl content ranged from 2% in winter to 10% in summer. The vegetation, in particular Salicornia fruticose (Sea Asparagus), forms, on the surface of the soil, a rather dense cover, very favorable to the development of some species of testate amoebae, represented by abundant populations.

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