Pseudoscorpions are small arachnids with a flat, pear-shaped body and pincers that resemble those of scorpions. They usually range from 2 to 8 millimetres (0.079 to 0.31 in) in length. The largest known species is Garypus titanius of Ascension Island at up to 12 mm.
The abdomen, known as the opisthosoma, is made up of twelve segments, each protected by plates (called tergites above and sternites below) made of chitin. The abdomen is short and rounded at the rear, rather than extending into a segmented tail and stinger like true scorpions (the fact that they look exactly like scorpions, aside from not having a stinger tail, is the source of the name "Pseudoscorpion"). The color of the body can be yellowish-tan to dark-brown, with the paired claws often a contrastiA pseudoscorpion has eight legs with five to seven segments; the number of fused segments is used to distinguish families and genera. They have two very long ng color. They may have two, four or no eyes.A pseudoscorpion has eight legs with five to seven segments; the number of fused segments is used to distinguish families and genera. They have two very long palpal chelae (pedipalps or pincers) which strongly resemble the pincers found on a scorpion.
The pedipalps generally consist of an immobile "hand" and "finger", with a separate movable finger controlled by an adductor muscle. A venom gland and duct are usually located in the mobile finger; the poison is used to capture and immobilize the pseudoscorpion's prey. During digestion, pseudoscorpions pour a mildly corrosive fluid over the prey, then ingest the liquefied remains.
silk from a gland in their jaws to make
cocoons for mating, molting, or waiting out
cold weather. Another trait they share with
their closest relatives, the
spiders, is breathing through
spiracles. However, they do not have
book lungs as most spiders do.