Mr. McFarland
11/16/14
Botany 111 003
My observations for this week were about what I expected. My food pellet that was placed in my aquarium was pretty much completely gone, but there was still a few small organisms feeding off of what was left of it. I knew that I wouldn't see as many rotifers this week just because of the decrease there was in them last week, but I struggled to find almost any rotifers. I asked Mr. McFarland to help me find some and we found one of the most strangest rotifer activity I saw in the five observations I did. When we were searching around for rotifer activity, we found a rotifer digesting algae. It was attaching itself so it could slowly digest the algae through its gut. In the picture below you can see the piece of algae attached inside of the rotifer. You could slowly see its body taking in the algae and breaking it down for digestion.
I also found an increase in the size of the euplotes. The Euplotes were also much more active than I had seen them in my weekly observations. While examining the Euplotes, I stumbled across an organism with Mr. McFarland that I had never seen in my aquarium. as we examined it, we noticed it was manipulating food particles front end where its mouth area, also called the bucoal canal was located and would then spit out the food. We also found an oval shaped red dot located in the middle of its body. We searched for the organism in the book but could not put a specific name for it. We decided to put it a common like name to the organism as Unknown Silliate (Patterson 143 fig 317). Below is the organism.
Another organism I found while looking at my aquarium was a Litonotus sp. I had trouble trying to get a clear vision on the organism and what its activity was because of its clear like body structures. When I did find a clear view on the organism, I found that it was using its vacuole to regulate water pressure by a constant contracting method it was using while moving along the aquarium. As I researched the organism more, I found that many of these organisms have two macronuclei in the center of their bodies along with a contractile vacuole that can be seen in the posterior of this region. The organisms are also described as having contractile bodies. The long neck like area on top of its body is the ingestion area for food consumption and digestion (Patterson 132 fig 286).
I also found the organism Centropyxis. When researched, I found that it is a testate amoeba. Its usually has a brownish tint to it which is because of the accumulation of metal ions from its environment. Its body is made up of a flat ventral surface with an anterior end. It's body is described as being shell like with a single aperture (Patterson 95 Fig 84). Below is a photo I took while observing its body structure and brown tint. I found it floating in the middle area of my aquarium near one the plants.
Sources
Patterson, D.J. 1992. Free living Freshwater Protozoa: A colour Guide. Washington D.C.: Wolfe Publishing LTD. 132, 143, 95 p