I discovered this conspicuous critter in the leaf litter at Kaweah Oaks Preserve in early January. It is a Red Velvet Mite, a large soft bodied Trombidiid Mite, possibly Trombidium sp. The body is covered with tiny red hairs, giving it an appearance of velvet.
These mites are slow moving creatures that have big appetites. Even the young mites prey upon insects many times their size, preferring grasshoppers and crickets. They also consume insect eggs.
Some mites are used for controlling many kinds of insect pests, so are considered beneficial to the environment. They are no threat to humans.