These red mites are perhaps the best known water mites since they are easily visible. They reach sizes up to 6 mm. There are several similar genusses. Mites from the genus Hydrachna are very common. When examined under the microscope the skin appears armored with a very fine spikes.
All water mites are predators.
They feed on all kinds of Crustaceans and larvae of water insects. The prey is grabbed by the pair of palps and the fluid content of the victim is being sucked out via piercing mouthparts. Image taken with a Leitz 6X achromat and 2.8 Olympus photo-ocular, mites size about 2.5 mm.