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Lesquereusia gibbosa
L. gibbosa, after Thomas and Gauthier-Lièvre, 1959

Lesquereusia gibbosa Thomas et Gauthier-Lièvre, 1959

Diagnosis: At the base of the neck there is a clear constriction, indicating an internal diaphragm placed at about half the width of the test. On both sides of the constriction, along the dorsal contour, there are two more or less protruding ridges.

Dimensions: Length 120-150 µm; width 100-140 µm; pseudostome 28-35 µm.

Ecology: Freshwater. Shallow clear ponds. Africa.

Remarks: Thomas and Gauthier-Lièvre: ‘The examined populations had varied coverings which are not without analogy with those which one observes in L. modesta: grains of quartz mixed with reworked more or less vermiculated xenosomes, which are elongated scales (transformed diatoms?), polygonal scales more or less imbricated on the edges, reshaped quartz grains, etc. Despite the analogy of form and covering with L. modesta, we believe that the tendency to form an internal diaphragm deserves to be taken into consideration; we base the creation of our species on this character. Let us also note that we found in our samples different variations in the morphology of the test: these are the classical variations that we observed in the different species, but they are always linked to the presence of the diaphragm.’

Thomas and Gauthier-Lièvre, 1959, distinguished some varieties, see below.

Reference: Thomas, R. et Gauthier-Lièvre, L., 1959: Le genre Lesquereusia Schlumberger 1845 (Rhizopodes testacés). Bull. Soc. d’Hist. Nat. l’Afrique du Nord, 388, 50: 34-86.

Lesquereusia gibbosa
L. gibbosa var. nodosa, after Thomas and Gauthier-Lièvre, 1959
Lesquereusia gibbosa
L. gibbosa, a-f. var. incisa; g. var. corniculata – after Thomas and Gauthier-Lièvre, 1959
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