It’s a thrill to find an organism in a natural setting ; and wonder if it’s something science and human society knows about or an undescribed, never before seen species. As a young Foldscope scientists, early on, you should not worry too much about this fact – since you are making discoveries without others telling you exactly where to look. This process of rediscovering knowledge from first principles is crucial as a training to be a good scientist. In fact, when Feynman rediscovered calculus as a kid – it probably shaped his thinking on how to think about the world in his own way.

With that as an introduction; I wanted to share a guide key to ciliates I often use when I stumble upon small “animacules” – single celled organisms swimming/moving around in water. It’s quiet a thrill to make the correct identification and I am posting this key for others to utilize as well.

To use the key, find the rough morphological match between your images/videos and what you see above – and look more deeply into the specific genra pointed above. Read key carefully and also note characteristics of live animals. You will find this very satisfying to make correct identifications.
The above key is courtesy [Corliss, 1979]. If you like; I find this book a fascinating read.

Go out and let’s see if you can find every single ciliate genera above.

Cheers

Manu