Mature males of this species have similar markings to a ladybird.
Females live for about three years. Males are shorter-lived and survive for less than a year.
Females are 8-16mm and males are 6-11mm. The females are usually black and mature males have red abdomens with four black spots (hence their common name).
Ladybird spiders are very rare in Britain and are possibly only found in Dorset. This spider is more commonly found around the Mediterranean.
They build a silk-lined tube on sunny slopes usually among stones or heather where they are protected from the wind.
Ladybird spiders hunt beetles and other spiders. They often catch tiger beetles, which are renowned for their aggressive and predatory nature.
Their vertical burrow is lined with silk. At the entrance is a tangle of strands of faintly bluish fluffy silk where insects become entangled. Females rarely leave their burrows.
When the male is mature he will leave his burrow and go in search of a female. After mating, the male dies and the female produces an egg sac which she camouflages with debris. She moves the egg sac to the top of her burrow during the day and brings it to the bottom at night. This probably helps to regulate the temperature of the eggs. When the spiderlings hatch they stay in the burrow with their mother until she dies. It is thought that the spiderlings feed on their dead mother before leaving the burrow.
They are a protected species in Britain under the Wildlife & Countryside Act 1981.