Squamamoeba japonica – from Kudryavtsev and Pawlowski (2013)

Squamamoeba japonica Kudryavtsev and Pawlowski, 2013

Diagnosis: measured length of the locomotive form 5.6-11.3 µm (average 8.1 µm), breadth 1.9-5.5 µm (average 3.5 µm), length:breadth ratio 1.25-4.5 (average 2.39) (n=112). Elongated flattened amoebae, oval or triangular during locomotion with anterior hyaloplasm occupying one-third to a half of the cell; hyaline subpseudopodia produced from the ventral surface of the cell have a shape of rounded granules when viewed from above. Single vesicular nucleus 1.5-2.5 µm in diameter (average 1.9 µm) (n=8) with inconspicuous central nucleolus 0.7-1.4 µm in diameter (average 1 µm) (n=7).
Cell coat a single layer of tightly packed scales separated from the plasma membrane, forming a number of papillate expansions along the cell surface. Scales flat, oval with the tiny filament arising from the center; scale size 95-145 (125) x 60-90 (75) x 10 nm (n=17).

Ecology: bottom sediments of the Sea of Japan, Pacific Ocean

Remarks: may resemble a small Pellita or a small Korotnevella but differs from the members of the former genus in the cell coat structure and uneven margin during locomotion, producing short subpseudopodia; differs from the latter genus in the presence of ventral subpseudopodia, tight connection of surface scales to each other and their separation from the plasma membrane, and formation of cytoplasmic projections protruding through the cell coat.

Literature: Kudryavtsev and Pawlowski, 2013


Squamamoeba japonica – from Kudryavtsev and Pawlowski (2013)
Recent posts

Difflugia key ovoid

Difflugia Ovoid Group Key characters: Test ovoid, in cross section rounded. Pseudostome circular. 1 Test with collar or short neck 2 1′ Test without collar

Read More »

Difflugia: ovoid tests

Difflugia – group 1 Test < 60 µm. Test in cross section rounded. Test with rounded fundus. Pseudostome with smooth circular edge. Test not spherical

Read More »

Difflugia ampla

Difflugia ampla, after Rampi, 1950 (l) and Gauthier-Lièvre et Thomas, 1958 (r) Difflugia ampla Rampi, 1950 Diagnosis: Test broadly pyriform, with a wide and rounded

Read More »