Behaviour

Footage of a newly-isolated, and as yet unnamed, marine relative of Arachnula impatiens recently found by researchers from the Natural History Museum in sediment samples collected in North Carolina. It illustrates the typical cell movement and hunting behaviour of Arachnula impatiens and other vampire amoebae.

Vampire amoebae have a specific way of feeding that has earned them their peculiar name.

Most predatory amoebae eat by engulfing a whole prey by a mechanism called phagocytosis - they surround the prey with their pseudopods until it is completely trapped inside the amoeba.

Vampire amoebae are unusual – they bore holes into the walls of filamentous algal and fungal cells and suck up their content (see figure 5). Sometimes the amoeba even penetrates the cell wall of its prey and eats it from inside.

All vampyrellids share this specialized feeding mode on algae and fungi, but some species like Arachnula impatiens can also feed in the more usual way by engulfing a whole prey (eg when feeding on diatoms or fungal spores).