Family Oonopidae (Goblin spiders)
Body length 1-2 mm.
Also known as the Pink Prowler, it belongs to a family of spiders called Oonipidae, of which there is one genus, and 2 British species. Oonops pulcher is the other species, and is generally found under bark, stones and leaves, where Oonops domesticus is found in buildings. To accurately identify them you would need a microscope, although Oonops domesticus has five tibial spine pairs where Oonops pulcher has four, and they do live in distinctly different habitats.
During the day it remains hidden in a silken cell behind furniture or in cracks in woodwork. Seen all year round.
It has six tightly clustered eyes, and is a creeping, stealthy hunter of small invertebrates like booklice and mites, interspersed with rapid movement. It apparently gently strokes its prey with outstretched legs before darting forward and biting it.
Because of its size and nocturnal habit it usually goes unnoticed in houses, and is probably under recorded. Widely scattered and uncommon in England, with few sightings in Scotland and Wales. A native species.