The Ceriodaphnia is a smaller cousin of the larger Daphnia magna and reproduces much faster.  The smaller size makes them a better choice for smaller breeds.  These are cultured in green water (chorella).  While I have known these to be ceriodaphnia some people refer to them as moina.  As to which one they are properly is not easy to know without being an expert at freshwater zooplankton. There are over 200 species of Daphnia and about 40 species of Moina.  As for which exact species these are, I dare not try to say.  

Daphnia can be a real advantage to fishkeepers, providing a tempting and nutritious supplement to traditional prepared fish foods. A type of freshwater zooplankton, daphnia are also known as water fleas, and even the most finicky fish will readily chase and eat them as they jump around in the water column.  Daphnia will not pollute the water in the tank, as they remain alive until they are eaten. They can be used to feed many different types of fish to get them into breeding condition.  Fry can benefit from daphnia, too. Place adult daphnia in a fry tank and they will drop young daphnia about the size of baby brine shrimp about every three days. As a bonus, the adult daphnia consume bacteria, thereby improving the water quality in your fry tank.