The specimen on this page came from a fresh water sample from China. I put the material in a petri dish and added demineralized water. This specimen lived for nearly four weeks in the dish before I couldnt find it back between the debris. It showed an elongated pointed fundus which changed in length over time. The aperture looked a bit like a funnel and could bend sidewards, with folds in the neck. Sometimes a bulge of protoplasma came out of the aperture where it stayed for many hours before it was retracted into the test. The specimen stayed in the same place for many days.
Typical funnel shaped aperture
A bulge of protoplasm in front of the aperture