This is a very diverse group of mainly very small amoeboids with very fine branching or unbranched filopodia (granulopodia) bearing granules (extrusomes) at frequent rather regular intervals, or with radiating, sometimes branched, axopodia with similar granules; the filopodia are supported by internal microtubules and are typically appressed to the substratum during feeding, in a semi-immobile state.
In most species the filopodia do not anastomose. Some species have a biciliated swimming or gliding stage.
Most species easily settle on the cover glass which offers an ideal optical position to observe and photograph them. If you want to see them, just keep your wet mounts for some days in a moisture chamber. Phase Contrast is also very useful