Post 3

     Observed on November 4, 2014

     I observed a much larger variety of different organisms this week that have yet to appear in my microaquarium, perhaps due to multiple pairs of eyes looking through the microscope this time. I observed Cyclops, Difflugia, Vorticella, Midge, and some other creatures I was unable to identify.  I was unable to capture a photo of the Midge.  I captured some nice photos this time around that turned out very clear.  

     The first photo below is of a juvenile Cyclops.  This organism's usual life cycle consists of the egg, six nauplius stages, five to seven copepodid stages, and the adult stage as well.  In some species this cycle is abbreviated with only four or five nauplius stages (Pennak, 1953).  These organisms accumulate calcium in the cortex.  They are scavengers feeding on dead and dying organisms (Patterson, 2003).

     The second creature I stumbled upon was Difflugia.  Difflugia is a shelled amoeba.  This common organism is shaped by pieces of 'grit'.  The body is round with a circularapical aperture and occasionally the posterior end is drawn out as a point (Patterson, 2003).

     The final creature that you see in the bottom photo is a Vorticella.  This organism is a a common peritrich ciliate.  The cilia that are active are wreaths of feeding cilia made of an upper band that corresponds to a membranelle and creates currents of water for food purposes.  There is also a lower band that corresponds to the undulating membrane.  These creatures can be vulnerable to predators, howver some protection is provided by stalk contractibility (Patterson, 2003).

     

     

Bibliography

Patterson, D.J. Free-Living Freshwater Protozoa. Washington DC: Wolfe, 2003. Print.

Pennak, Robert W. Fresh-Water Invertebrates of the United States. New York: Ronald, 1953. Print.