Pseudoscorpions look like very small scorpions with an oval, flattened body. Like the latter, they carry a pair of large pedipalps terminated by claws. On the other hand, they do not have a sting at the end of their abdomen and the rear end of their body is short and rounded (it is elongated to form a suchon in true scorpions). They are on average 2 to 4 mm long. No known species measures more than 8 mm.

Pseudoscorpios have two or four eyes, sometimes none. Their coloring varies from yellowish beige to dark brown. The pincers are sometimes black. The male and the female are similar.

Small, very efficient pliers

The pincers of pseudoscorpions carry at their end (usually on the mobile part) a well-developed poison gland. This gland can be found on both clamps or on just one. Pseudoscorpions use their pedipalps to catch their prey, which is then paralyzed or killed by the venom.

Once paralyzed, the prey is seized by the chelicerae, these two hooks located on either side of the mouth, which tear its exoskeleton. As in the spider, the pseudoscorpion sucks up predigested substances, because part of the digestion takes place outside, in the body of the prey. When it sucks up its prey, hairs filter the solid particles to allow only liquids to pass through. When there are too many particles accumulated, the pseudoscorpion ejects them. After eating, he cleans his intricate mouthparts using comb-like structures located on the chelicerae.

Pseudoscorpions wear their pedipalps in front of their heads as they move. If disturbed, they bring the claws back above their shell and stop. They are able to move backwards.

Pseudoscorpions have glands that produce the silk threads for making their cocoons. The opening of the duct of these glands is located on the chelicerae.