Jul 26-28, 2008
This was from a pool near Fish Creek, with clear water but many large clumps of algae floating or growing on the bottom. The sample was one of the floating mats, a sticky tangled mass of Rhizoclonium with a few duckweeds. A number of arthropods were also present – water fleas, copepods, amphipods, and midge larvae – as well as a few pond snails.
The most activity was around the duckweed, with abundant flatworms of varying size and Paramecium, both green. There were also groups of small prostomes, and various sessilids, among others. Paramecium and prostomes also occurred throughout the sample, along with Halteria, Frontonia, Lepadella, and bdelloids.
Besides these there were scattered Cothurnia, diatoms, and small oval ciliates on the algae, and ostracods, Anthophysa, and filamentous cyanobacteria near the bottom. In each of these sections there were also many other kinds that were only noticed once or twice.
↬ Thanks to Michael Plewka, author of plingfactory: life in water, for the identification of Cephalodella.
Gently turning - about 45 µm
Non-motile - dark spheres up to 45 µm
Stationary but later rounding out - about 70 µm
More or less turning in place - about 120 µm
Slowly turning with fine cilia - about 165 µm