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Genus Polychaos Schaeffer, 1926

Diagnosis: during active locomotion usually polypodial, palmate, with several tubular pseudopodia, more or less equal and with no one dominant, proceeding anteriorly and anterior-laterally from common posterior mass; posterior of cell often with a bundle of fused, remnant pseudopodia; pseudopodia sometimes flattened and broadening towards ends; monopodial in rapid locomotion with a bulbous uroid; no dorsal ridges; nucleus granular or with other arrangements of nucleolar material; crystals irregular or plate-like to bi-pyramidal, some as paired bodies or clusters.

Key to the species:

1 Nucleus with a ring- or belt-shaped nucleolus

2

Nucleus granular

3

2 Nucleolar material in few narrow peripheral lobes, sometimes in a single curved band, twisting inside the nucleus. P. fasciculatum
Nucleolar material forming a perforated sphere inside the nucleus.

P. annulatum

3 Nucleus discoid, spheroid or ovoid P. dubium
Nucleus shallowly to deeply cup-shaped P. nitidubium
Polychaos annulatum
Polychaos fasciculatum
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