Synura sp. Chrysophytes or Golden Algae, are common in freshwater habitats especially in spring. These motile spherical colonies have yellow brown plastids, two flagella of different length and are covered with siliceous scales.
Synura is a genus of colony-forming autotrophic organisms in which a variable number of cells are joined together at their posterior ends. Each cell is covered by imbricate silica scales, whose ultrastructure essentially defines the particular species. Several scale types occur on the same cell, depending on their position. Apart from the prevailing body scales, apical and rear scales can also be observed and are characterized by their different length to width ratios.
The algae in this video are taken from a small garden pond in March 2017 in The Netherlands. A quantity of 100 ml sample was taken with a trawl, with a mesh size of 35 microns. The sample was again passed through a sieve with a mesh size of 30 microns. About 3 ml residue was transferred into a culture dish with a bottom provided with a calibrated cover glass. The freely moving algae were filmed by means of a Motic inverted microscope with 10, 20 and 40X Motic PlanApo objectives.