One of the UK's largest spiders in body area (some 20mm), as illustrated on the boot below, is the female Araneus quadratus.
The male is much smaller. Colour varies from yellowish green to reddish brown;
its 4 white spots are more visible on the darker greens and browns. The female can change her colour over several days to match her
surroundings and builds an orb web to catch grasshoppers and small insects with a side funnel retreat.