What is Microworld?

Microworld is my personal window into the hidden world of amoeboid organisms. On this site I share what I’ve discovered over many years of observing these remarkable creatures — in drawings, and in more than 10,000 photomicrographs and videos.

The site also contains a growing database with descriptions of 1803 species. New information is added regularly. Even though biology has advanced enormously in recent decades, we still know surprisingly little about free‑living amoebae in their natural environment. When you first start looking at them, everything may seem clear and easy to identify. But the more you explore, the more questions appear. Many older species descriptions are vague or incomplete, which makes identification a real challenge.

The menu follows modern taxonomy, which may take some getting used to. To help you along, you’ll find both dichotomous keys and visual keys for identification.

If you have comments, suggestions, or questions, I’m always happy to hear from you.

Citing Microworld

Cite Microworld as: Siemensma, F. J., Microworld, world of amoeboid organisms. World-wide electronic publication, Kortenhoef, The Netherlands. Accessed July 14, 2026.

Copyright

All images on Microworld are my property unless otherwise stated. Any copying or downloading of these images, by any means, for commercial or non‑commercial use without my written permission or the permission of the copyright owner is illegal.

© Ferry J. Siemensma