Family Amoebidae Ehrenberg, 1838

Diagnosis: Locomotive amoebae usually greater than 80 µm in length, with cylindrical pseudopodia with hyaline caps. Some species monopodial but most polypodial. Many have cytoplasmic crystals. Nucleus often with nuclear material in small fragments.

Key to the genera of family Amoebidae

1Amoeba multinucleate

2

Amoeba usually with one nucleus

3

2Amoeba usually polypodial, with longitudinal ridges

Chaos

Amoeba usually monopodial, without longitudinal ridges

Parachaos

3Amoeba monopodial, only branched when changing direction

4

Amoeba usually polypodial

5

4Amoeba free-living

Trichamoeba

Amoeba parasitic on freshwater coelenterates (hydra)

Hydramoeba

5One dominant leading pseudopodium with smaller lateral pseudopodia

6

Pseudopodia more or less equal-sized, radiating from a central mass like the fingers of a hand; villous bulb uroid

Polychaos

6Amoeba usually > 200 µm; nucleus granular

7

Amoeba usually < 200 µm; nucleus with few nucleolar pieces

Deuteramoeba

7With longitudinal ridges

Amoeba

Without longitudinal ridges

Metachaos

Recent posts

Difflugia symoensi

Difflugia symoensi, from Chardez, 1964 Difflugia symoensi  Chardez, 1964 Diagnosis: Test bag-shaped, with pseudostome almost as wide as the width of the test; fundus rounded.

Read More »

Difflugia tenuis

Difflugia tenuis, from Penard, 1890 Difflugia tenuis  (Penard, 1890) Chardez, 1983 Diagnosis: Test cylindrical or slightly pyriform, fundus often more angular then rounded, very transparent

Read More »

Difflugia gigantea

Difflugia gigantea (left) compared with other species to show its size Difflugia gigantea Schlumberger, 1845 Diagnose: test ovoid, elongated, narrowed anteriorly, almost pyriform, sometimes slightly

Read More »

Difflugia masaruzzii

  Difflugia manicata, test and nucleus – after Van Oye, 1958   Difflugia masaruzzii  Van Oye, 1958 Diagnosis: Test more or less ovoid with lateral

Read More »