Vinegaroon

No. Vinegaroons have no venom glands anywhere in the body and no sting — the "tail" is a thin, flexible, whip-like sensory filament, not a weapon. Their only chemical defence is the acetic-acid spray, which is an irritant, not a toxin — it stings and can burn if it gets into your eyes or an open cut, and it makes the animal taste and smell terrible to a predator, but on intact skin it is roughly like getting splashed with strong vinegar. A large vinegaroon can also give a firm pinch with its heavy pedipalps if handled roughly. They are shy, slow, nocturnal, and are widely kept as docile pets. The alarming folk names — "whip scorpion," "mule killer," "grampus" — reflect their fearsome look, not any real danger.

A pair of glands opening near the base of the tail (at the rear of the abdomen) produce a fluid that in the best-studied species, Mastigoproctus giganteus, is about 84 percent acetic acid — the acid that makes vinegar sour — mixed with water and a small amount of caprylic acid, an oily compound that helps the acid soak through the waxy outer layer of an insect's cuticle. When threatened, the vinegaroon raises and swivels the tip of its abdomen and its tail to point at the attacker and releases the fluid as a fine, aimed spray or mist over a range of a few centimetres, and it can fire repeatedly. The whole area, and often the animal itself, then reeks of vinegar for some time.

They are related — both are arachnids in the broad "whip-bearing" group — but they are different orders and easy to tell apart. A vinegaroon (order Thelyphonida) has a long, thin, jointed tail (the flagellum), a stout scorpion-like body, heavy crushing pedipalps, and the acetic-acid spray glands. A tailless whip scorpion (order Amblypygi) has no tail at all, a very flat body, long spiny grabbing pedipalps, and — most obviously — one pair of legs drawn out into extremely long antenna-like feelers. Neither has venom or a sting, and both are harmless nocturnal predators, but only the vinegaroon sprays acid.

Yes, they are a popular and rewarding beginner arachnid. They are hardy, long-lived, slow-moving, and not prone to biting or spraying unless genuinely provoked, and a large species like the giant vinegaroon is impressive to look at. They need a deep layer of moist substrate to burrow into, a hide, warmth, moderate to high humidity, a water dish, and a few appropriately sized live insects each week. They should be kept singly outside of breeding attempts, and handled low over a soft surface and infrequently, both to avoid startling them into spraying and because a fall can injure them. After a female produces young she usually declines and dies, which keepers should expect.