Red velvet mites or rain bugs are arachnids found in soil litter known for their bright red color but are often mistaken for spiders. They are called Laal Gaay or Gokul Gaay in Hindi, Sadhaba Bohu in Odia, Arudra and Kumkuma purugu in Telugu, Indragop and Mirag in Marathi, and Pattu Paapaathi Poochi in Tamil, Beer Bahuti or Birboti in Urdu and Birbaboti in Dakhni. They are active predators as grown adults but as early instars are often parasites on insects and some arachnids.

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.

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

The oil from the red velvet mite Trombidium grandissimum is used in traditional Indian medicine to treat paralysis.
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