Week 4: Observing the Aquarium

Today, when I examined my microaquarium, it was full of many organisms. A majority of the organisms have moved to the food pellet and have been moving around it. Many of these organisms are small and circular, but there are a few larger organisms as well.

One of these larger organisms that I found was an aeolosoma. These organisms are a type of annelida that are strictly aquatic (Pennalt 1989; Fig. 1, 291). The organism is sometimes found in mud and debris, but in this case was found in masses of filamentous algae. By looking at the picture below, it is easy to see its internal organs, which is a common trait of its species.

Aeolosoma:

Aeolosoma (Head):

Another rather large organism was a seed shrimp. Seed shrimps are seldom more than 3mm long and, in this case, are a dark brown (Pennalt 1989; Fig. 444). It has a lime-impregnated valve that consists of an inner and outer plate. Between these two plates is a skin fold that secretes value materials. They mostly eat bacteria, algae, molds and find detritus.

Seed Shrimp:

The smaller organisms consist of several euplotes. These particular euplotes have cilia and have a structural groove (Patterson 1998; Fig. 260). They are a type of hypotrich cilate and can make a current of water using membranelles. There are also ventra cirri on the organism.

Euplote:

Multiple Euplotes: