Hedriocystis species feed on bacteria. I made some photomicrographs of the capture of a bacterium by a specimen of  Hedriocystis brachypous. All pictures were made with a Leitz 100X Oil Phaco objective.

Hedriocystis brachypous
The shell is 13.0 µm in diameter. The arrow points to a bacterium (here out of focus) that touched one of the kinetocysts. These granules on the axopodia can paralyze a prey.
Hedriocystis brachypous
This sequence of pictures shows how the axopodium makes a cup-shaped pseudopodium which encloses the paralyzed bacterium in a vacuole.
Hedriocystis brachypous<


This sequence shows how the bacterium in the vacuole is transported along the axopodium into the shell and finally into the cytoplasma.
Hedriocystis brachypous


A last view of the bacterium before it disappears in the cytoplasm to get digested.
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