Main Content

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Ref ID : 4248

Ronald E. Martin; Adhesion, Morphology, and Locomotion of Paramoeba pemaquidensis Page (Amoebida, Paramoebidae): Effects of Substrate Charge Density and External Cations. J.Protozool. 34(4):345-349, 1987

Reprint

In File

Notes

Morphology and locomotive behavior in the marine amoeba, Paramoeba permaquidensis Page, was examined under different environmental conditions, Paramoeba requires a minimum surface negative charge density for adhesion of amoebae to substrata. Once adhension to the substratum has been attained, however, surface negative charge density has no effect on morpholgy or locomotive rate. Divalent cations are not required for adhension, but external calcium is required for normal locomotion. In the presence of calcium, Paramoeba often assumes a locomotive form with a broad, well-developed anterior hyaline region and truncate posterior region. Locomotive forms vary from those with only a well-developed hyaline region (Flabellula-like) to forms with long digitiform subpseudopodia (Vexillifera-like), with intermediate morphotypes. Locomotive rates decrease and anteroposterior polarity disappears in the presence of living or heat-killed bacteria, indicating that phagocytosis temporarily interferes with locomotion and alters form.