A cyclops, freshwater copepod. The size of the animal is about 0.5 mm. It is a female carrying eggs. A close observation can reveal red dots inside the eggs. The red dots are the single eyes of the developing babies.
Moina micrura, a water flea. The size of the animal is about 0.5 mm. Inside the crustacean there's a resting egg visible (on the right side), which is called ephippium. This is a sexual stage in their reproductive cycle. Water fleas usually reproduce asexually, however, in autumn or in harsh environments they switch to the sexual reproduction and an ephippium is formed out of a fertilized egg.
Ceriodaphnia sp., a water flea. The size of the animal is about 0.5 mm. The surface of the shell is clearly visible as well as a couple of limbs with muscules inside.