cortex

Description:

Nassulopsis (nass-you-lop-sis). Nassulopsis elegans is a conspicuous pink- or blue coloured nassulid found in pond and lake plankton. This cell was collected from floating colonies of Oscillatoria in a freshwater pond near Konstanz, Germany. The body is cylindrical in shape and measures 150 - 300 X 50 - 100 microns. Nassulopsis can be distinguished from Nassula and Obertrumia by 5-7 contractile vacuoles arranged in a ventral row. The macronucleus is cylindrical with rounded ends. The cytopharyngeal basket is located in the anterior third of the cell. The cells fill up with food vacuoles of different colour (green, orange), depending on stage of digestion. This picture shows the pellicle of Nassulopsis elegans with its net like ornamentation. A mucocyst lies at the centre of each square. Differential interference contrast.