Ballus chalybeius

Ballus chalybeius is a jumping spider. It is the type species of the genus Ballus.

Appearance
This flattened spider can reach a length of 3 –. The prosoma is dark brown in females, with irregular lighter markings. The lightly yellow legs have dark rings in both sexes. In males, which are generally darker, the first legs are dark and thickened. The species is similar to Ballus rufipes, which is smaller and much darker.

Habits
During summer, the female builds a flat silken retreat on the underside of a leaf and guards its egg sac inside.

Habitat
It can be found mostly on the fringes of deciduous forests, on broad-leaved bushes and trees, particularly oaks, and in the grass. In Central Europe, they are widely distributed and in most areas quite common.

Distribution
Ballus chalybeius occurs in Europe, North Africa to Central Asia.

Name
The species name is derived from Ancient Greek chalyb- "steel".