world of amoeboid organisms

Pontigulasia pentangulostoma
P. pentangulostoma, after Quin et al., 2008

Pontigulasia pentangulostoma Quin et al., 2008

Diagnosis: Shell is brown, laterally uncompressed, parted to neck and body regions with a distinct constriction; it is circular in cross section. The body is comparatively globose and narrowed generally towards the constriction (Figs 1–5). The neck is also circular in cross section, but the aperture has five angles and five borders, like a pentagon, surrounded by some irregular arrangement of small particles. In apertural view, at the junction of the neck is an internal transverse loop, extending from side to side coextensively with the constriction, to give this species its characteristic shape. The surface of the test is more or less thickly incrusted with different size of sand-grains and other material, bound by a network of organic cements (Figs 1–5).

Dimensions: Length 201-281 µm; width 156-209 µm; neck length 50-67 µm; aperture 41-67 µm.

Ecology: In sediment of Sphagnum dominated (oligotrophic) peatland.and aquatic vegetation in shallow water.

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