Red Velvet Mites or Rain Bugs are arachnids found in soil litter known for their bright red colours but are often mistaken for spiders. They are active predators as grown adults but as early instars are often parasites on insects.

The pattern of stages is shared with that of other members of the Prostigmata: egg, pre-larva, larva, protonymph, deutonymph, tritonymph and adult (male or female). They usually have only one breeding cycle per year.[2]

One well known species from the Palearctic is Trombidium holosericeum.

The systematics of this group has been in flux and many former subfamilies of this are now raised to families within the Trombidioidea.[2]

The oil from the red velvet mite Trombidium grandissimum is used in traditional Indian medicine to treat paralysis. Also, due to their alleged ability to increase sexual desire, Trombidium mites are known locally as "Indian Viagra."[3]

The tiny red velvet mite, belonging to the family Trombidiidae are not much bigger than the head of a pin. Despite this, it is one of the largest species of mites known to us. Furthermore, there are thousands of species of the red velvet mite itself. These mites are bright red in color and their bodies are covered with very fine hair to give them a velvety appearance. Hence, the name red velvet mite. Given below are some facts about the red velvet mites. Generally, the red velvet mites are found in dry environment such as deserts. But, they are also found in soil litter as well as on plant leaves and logs of decaying wood.

It has been observed that the red velvet mites live under the surface of the earth until it starts to rain. Once it rains, they suddenly emerge from beneath the ground in large numbers. The gestation period is about one or two months. Once the eggs hatch, the larvae come out but do not disperse immediately, they stay there for a few days. This is the pre-larva stage. The larvae are parasitic in nature, and feed on hosts such as crickets, dragonflies, grasshoppers, etc. Once they grow up to become adults, they hide themselves underneath the ground and emerge after it rains.[10]

Red Velvet Mites, one burrowing after rain. Cochise, Arizona, Chihuahua Desert. 2018