Apr 28-29, 2019
This was from a broad pool in a grassy field. The day before everything had been carpeted by a late snow storm, filling the margins with greyish slush and now melting. Some of the fairly clear water near the edge was taken along with strands of grass, which were still dead and brown from last year.
The settled debris was rich in algae, especially globular colonies, gliding diatoms, and flagellates like Phacus, Cryptomonas, and Lepocinclis among others. There were also a reasonable number of amoebae like Arcella, Acanthocystis, and some unanchored Clathrulina, feeding on many tinier moving cells.
The main ciliates were large sessilids, most staying in place but with posterior cilia and no visible stalk. Rotifers like Lepadella were common, and even more so were copepods and their larvae, found throughout the sample. Larger animals included a few water scavenger beetles and a pond snail.
↬ Thanks to protistologist Dr. Ferry Siemensma, author of Microworld: world of amoeboid organisms, for the identification of Acanthocystis and to Roman Romanov for the identification of Woronichinia.
- colony about 150 µm
Cyanobacteria - sections about 25-35 µm
Cyanobacteria - clumps about 65, 185 µm
Cyanobacteria - sections about 55-70 µm
Nostocales - about 6-9 µm wide