Freshwater rotifer Philodina gregaria. This is a very common species for Antarctica. Sometimes the number of these invertebrates is so high that it makes the water look rusty.
An unidentified diptera larva. It's a transparent worm-looking creature with guts and circulatory system clearly visible. It's a single shot made in polarized light. Stacking was impossible with this highly active animal.
Gyrosigma diatom algea
