This animal belongs to the Phyllum Rotifera, (Latin <em>rota</em>: wheel + Latin <em>fera</em>: those that bear) derive their name from the characteristic ciliated crown, or corona, that you can see beating in this drop of water that I collected after a heavy rain in Mexico City. You can see this ciliated crown which gives the impression of rotating wheels in this short video. This mechanism is used to get their food from their environment they live. Rotifers range from 40 μ m to 3 mm in length, but most are between 100 and 500 μ m long.

Photo by Daniel Zamora Mejías