Lab Observations 4

Made: 11.5.13.
        Things in the aquarium are getting bleak. Upon viewing my MicroAquarium today, it was clear that a lot of the life previous filling the tank is now dead. The food pellet has virtually dissolved, taking with it the activity and business of last week, especially around the plant samples, which are covered in little debris particles. It looked deserted. I looked at my microscope for a long time before seeing any movement besides the small organisms such as Coleps sp. that are always around, and even those were notably decreased (Rainis & Russell 1996) . Due to the lack of activity and age of my aquarium, I looked in the debris at the bottom, and finally noticed definite dead organisms. I also never saw any of the same organisms, save for a few Cyclops sp. samples, including a juvenile, some Vorticella sp. (in their clusters) (Rainis & Russell 1996), and either two or three samples of Euchlanis sp. (Pennack 1953) . It is unclear if any of these were ones I viewed in previous lab sessions. It is safe to say the the number of most of my organisms have went down, though eventually, new types of organisms were sited.
          The behaviors and physical appearance of organisms I have already identified maintained constant in that the organisms moved and looked the same as before. I even saw a couple of organisms with the naked eye again and, as before, was unable to "catch" them with the microscope, though I believe them to be Cyclops sp. samples (Rainis & Russell 1996). However, each new organism discovered today was interesting, and makes me question why they appear at this stage of the aquarium's life, when all else seems to be dying. Of those viewed today the most interesting has to be the discovery of Craspedascuata sp., featured in Figures 1&2, which stirred up a lot of curiosity (Pennack 1989).

Fig. 1. Shows colony of  Craspedacusta sp.
with two poms. (Pennack 1989). 

Fig 2. Shows Craspedacusta sp.
in polyp form (Pennack 1989).

      When I first found it I thought it might be some sort of basidiomycete, as it's structure reminded me of a toadstool with typical pilus/gill formation. It was residing on the side of the Fontanalis sp., wasn't moving, and appeared to go through the plant (McFarland 2013). It had poms on either end and another slightly above. It was multi-cellular and the pattern of it cells seemed to indicate it had plant cells almost. Dr. McFarland looked under the microscope and even he could not identify it. It took much questioning and referencing to identify the organism correctly and it was mistaken for many things. However, eventually we discovered a hopeful contestant, Craspedacusta sp., a jelly-fish like organism that will form a polyp by sexual reproduction via budding (Pennack 1989). The figures presented bore resemblance and made me hopeful that one of the little poms was in fact, a budding polyp in the make. To be sure our observations were correct, I searched the web for more information on this species. I have referenced two cool depictions of the Craspedacusta sp. (Pennack 1989), including one of it's life cycles, in figures 3 & 4. I also learned from this site that the medusa have been shown to ingest different zooplanktons (Branson 2009). This is a little sad because my tank is already barren and I'm afraid the jellyfish will finish it off.

Fig 3. Shows a colony of Craspedacusta sp.
and budding medusa. (Branson, 2009).

Fig. 4. Shows Craspedacusta sp. life cycles,
including sexual which produces medusa (Branson, 2009).

            Besides the discovery of  the Craspedacusta sp., some other really neat organisms were quite abundant in the aquarium (Pennack 1989). The creatures I am speaking of are small, circular bodied organisms with many spike looking protrusions, much like a little sunburst or some kind of cuckle burr. I have documented a picture of Acanthinocystis sp. (Fig. 5) specifically, but there were many of this same type of organism throughout the tank. They were located mostly around the plant life, which Dr. McFarland noted meant they were hanging around for food. The Acanthinocystis sp. displayed a very still movement (as did all types of these organisms) and is shown below (Patterson, 2003). At least two of the Acanthinocystis sp. were viewed today. The spikes, according to Dr. McFarland, are used to capture and absorb/digest organisms.

Fig. 5. Shows Acanthinocystis sp. with long spiky protrusions (Patterson, 2003)

            Last but not least, I took note of at least two Diffluglia sp. (Patterson, 2003). One of which was growing and living and the side of the Fontinalis sp. (McFarland 2013). They had very slight, slow, drifting movements, and tended to sick to stem of the Fontinalis sp. (McFarland 2013).
           Also observed today were many structures called "rhizoids" which grow off of the plants in the tank. They look almost worm-like and I ended up confusing one for another Craspedacusta sp. at first. (Pennack 1989). Most of the movement of the day took place in the bottom of the tank, though organisms were observed near the plant sample (middle of the tank) as well. My aquarium contains both multi-cellular organisms, like the Craspedacusta sp., and unicellular organisms (Pennack 1989). Many of the organisms I viewed today were stationary, either because they were well...dead, or, as in the case of the sunburst organisms  like Acanthinocystis sp., they just didn't seem to be MOVING and instead sat mostly still (Patterson 2003).