Protozoa
 

Richard Howey's HomePage  

This page is devoted to showing a few of the incredible types of protozoa which are around us everywhere and go largely neglected.

 

 A small amoeba with a very ambitious appetite in the process of ingesting a long piece of a filamentous alga.


Another small freshwater amoeba which has an appetite for diatoms.


This is the flagellate Euglena acus; you can see it cholorplasts, its red eyespot and one of its two flagella.


The ubiquitous Paramecium photographed using Nomarski Differential Interference Contrast.

A Hypotrich which has bundles of fused cilia which form thicker cirri on which the organism can crawl around on the substrate. 

 

 

An undentiified leaf-shaped flagellate with a very long flagellum.



An intriguing and unusual organism with long, multiple flagella.  It belongs to the genus Streblomastix and is a symbiont which live in the gut of termites.  Without them and other related flagellates, the termites would starve to death, since they cannot digest cellulose.  The flagellates are able to metabolize it and produce starches and sugars which are utilized as food by the termites.


Another termite symbiont called Trichomitopsis. Note the undulating ridge on the "back" which when it is active gives it the appearance of a miniature saw.



This extraordinary creature, Trichonympha, is also a termite symbiont.  Note the large number of flagella and the large oval nucleus just above center.  


Another view of Trichonympha.


A closeup of the anterior end of Trichonympha showing the rostrum (the dome-like structure at the far right), the nucleus, and the elaborate system of fibrils and flagella. Interestingly Trichonympha does not feed from the anterior end, but rather absorbes wood particles through the membrane at its posterior. 


A closeup view of the shelled amoeba Arcella.  You can see a sizeable opening on the underside. The Arcella extrudes itself through this opening and extends pseudopodia to capture prey.  This shell is empty. On the surface you can see small diatoms and some fan-shaped mineral crystal deposits.


This organism belongs to the genus Thecamoeba and is fairly common in soil cultures.  It has a number of small vaculoes in addition to the large one on the left.  What appears to be a small vacuole just below the center is the nucleus. This beastie feeds voraciously on algae. I added a drop of the stain Neutral Red to the culture. It is a vital stain and relatively non-toxic.  As you can see the filamentous algae absorbed it strongly thus showing the filaments sharply with in the amoeba.  If you look carefully, you will see that vacuoles have also formed around these filaments.

Remember in the very first image at the top of the page, we observed an ambitious little amoeba attaching a long algal filament.  Here we find an even more ambitious small amoeba which is try to ingest a hypotrich which is larger than it is.  The remarkable thing is that it has a fair chance of success.