Identify It > Invertebrates Section > Pseudoscorpions >
Scientific name: Order Pseudoscorpionida
Size: Up to 4.5mm long depending on species
Distribution: Found throughout the UK
Months seen: All year round
Habitat: Sand dunes, leaf litter, under loose bark, in moss and lichen, under stones, in old bird nests, compost heaps and sometimes in houses
Food: Tiny creatures such as mites and springtails. The pseudoscorpion injects digestive fluids into its prey, and then sucks out the liquefied tissues
Special features: Pseudoscorpions are tiny invertebrates which closely resemble scorpions, except that they lack a stinging tail. They're rarely seen because they're secretive creatures and very small.
Pseudoscorpions belong to the same class of animals as spiders (Arachnida), and like spiders their body has two parts. The front part is called the prosoma, and the back part is called the opisthosoma.
They have eight legs plus a pair of pedipalps which are eqipped with pincers (like a scorpion). The pincers are mainly used for catching and grasping food. Some species of pseudoscorpion have no eyes, others have one pair and some have two pairs.
Pseudoscorpions are able to make a nest from silk which they spin from a gland in their mouth. The nest is used for shelter, breeding and moulting.
There are 26 species of pseudoscorpion living in the UK, and around 12 of these species are quite common. One species (Cheridium museorum) can be found in old libraries where they feed on book lice.