Genus Dinothrombium - giant velvet mites

rain bugs

s.CA to w. & s.TX / Mex. - Map (BG & GBIF data)

From (1):

Dinothrombium spp. live in sandy soil or sands in semi-desert or desert areas.

From (1):

Larvae are parasitic on various arthopods (Orthoptera, Coleoptera, Lepidoptera, Araneae and Solifugae).

Adults are predatory on termites.

Both larvae and adults can also be cannibalistic.

From (1):

The life cycle sequence is: egg, pre-larva, larva, protonymph, deutonymph, tritonymph and adult males and females. Pre-larvae, protonymphs and tritonymphs are calyptostatic, whereas larvae are ectoparasites, and deutonymphs and adults are free-living predators.

Adults only emerge from the ground and become active on the surface after heavy rain, when termite prey are swarming.

As part of mating, males and females perform encircling dances, during which pair-dance signalling threads are deposited.

Females are extraordinarily fecund, one species (D. tinctorium from Africa & India/Burma) produces on the order of 100,000 eggs.

From (1):

The bright red color is aposematic...adults Dinothrombium were offered as prey to many species of entomophagous animals but were rejected by most and spat out by those few that took them.

Lighton, J.R.B. and F.D. Duncan (1995). Standard and exercise metabolism and the dynamics of gas exchange in the giant red velvet mite, Dinothrombium magnificum. Journal of Insect Physiology 41(10): 877-884.

Newell, I.M. and L. Tevis, Jr. (1960). Angelothrombium pandorae n.g., n. sp. (Acari, Trombidiidae), and notes on the biology of the giant red velvet mites. Annals of the Entomological Society of America 53: 293-304.

Tevis, L., Jr. and I.M. Newell (1962). Studies on the biology and seasonal cycle of the giant red velvet mite, Dinothrombium pandorae (Acari, Trombidiidae). Ecology 43(3): 497-505.

Fact Sheet on genus Dinothrombium

Art Evan's Blog post on a Giant Red Velvet Mite found in AZ.