Sonoran Vinegaroon

Mastigoproctus tohono

VinegaroonbeginnerHarmless

No venom, no sting

Vinegaroons are harmless to humans — no venom and no sting. If threatened they can spray a fine acetic-acid mist (it smells like vinegar) and give a firm pinch, but neither is dangerous. Avoid getting the spray in your eyes.

Sprays acetic acid

Can spray a fine, concentrated vinegar mist when threatened. Not dangerous to skin, but genuinely painful in the eyes — keep it below face level when handling.

About

The southwestern US vinegaroon (split from the giant vinegaroon), often with a reddish tint. Docile and slow to use its acetic-acid spray — harmless to people (only irritating if it reaches the eyes). No venom, no sting. From arid country that wakes up in monsoon season, so give deep substrate kept dry on top and damp below for a humid burrow, plus a water dish. Room temperature is fine.

Taxonomy

FamilyThelyphonidae

GenusMastigoproctus

Native regionArizona, New Mexico, northern Sonora

TypeFossorial

Temperamentdocile; rarely sprays

Size & growth

Adult size~2.2 in body (plus tail)

Body length2.2–2.32 in

Growth rateslow

Life stagesNumbered instars

Climate

Temperature72–88°F

Humidity50–70%

Enclosure

Adult sizeterrestrial tank with deep substrate

Substratedeep moist coco/topsoil for burrowing; hide; water dish

Substrate depth4-6 inches

Water dishRequired

Feeding

Feeding modePredator (live prey)

Prey sizecrickets, roaches

Adult cadence1 prey per week

Times kept: 0