world of amoeboid organisms

Hoogenraadia alta
P. alta – from Bonnet, 1984

Planhoogenraadia alta Bonnet, 1984

Diagnosis: Test in dorsal view ovoid and a simple, not very well developed cryptostome. In side view, the test is rather broad, up to half the length. The fundus is more or less obliquely truncated so that the ventral side does not reach the end of the test. The invagination between belly and visor is reaching up to 1/3 of the total width of the test. The ventral lip is very little folded inward. In ventral view, the aperture is wide open and crescent-shaped. Small teeth (at the limit of visibility with the light microscope) are present on the edge of the dorsal lip or visor. There is a slight wall thickening at the level of the visor.

Dimensions: Length 89-125 µm; width 60-65 µm; height 56-85 µm; aperture 33-35 µm.

Ecology: Forest soils to soft humus. This species is often accompanied by Pseudawerintzewia calcicola. Tropical climate Regions: Nepal (low-level), Thailand, Indonesia, New Guinea (Papua).

Remarks: This species, of which the general shape is reminiscent of Hoogenraadia humicola, differs from the latter by its flat ventral side and its typical cryptostome.

References: Bonnet, L. (1984) Nouvelles données sur le genre Planhoogenraadia (Thécamoebiens). Bull. Soc. Nat., 120: 117-122.

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