Clover mites
The Clover mite, Bryobia praetiosa, is a type of mite best known for the reddish stain left on surfaces after being crushed. Clover mites are 1/30 inch long, oval shaped arachnids with a pair of long legs pointing forward often mistaken for antennae. They are reddish-brown; the younger ones and the eggs are a bright red.
Habits
Clover mites feed on sap from grasses and clover, and are especially numerous in lawns with a heavy growth of succulent, well fertilized grass.
They do not cause any apparent harm to turfgrass; however, their feeding activity can turn the grass a silvery color and may stipple plants when heavy populations are present.
Clover mites can become a nuisance in and around houses. They generally enter houses close to thick vegetation and can infiltrate houses in very large numbers through cracks and small openings around windows and doors. Whether indoors or outside, clover mites are found more commonly in sunny areas than in darker areas.