Ground crab spider (Xysticus)

Description:

The spiders of the genus Xysticus do not build webs; they are ambush hunters and prefer to hunt near the ground (hence the common name "ground crab spiders"). They move slowly, and commonly hunt by stationing themselves in a high-traffic area and grabbing whatever arthropod passes close enough. Also like most other Thomisidae, they seize prey with their enlarged anterior two pairs of legs and kill it by a venomous bite.

Notes:

First photo was actually the last photo I took; it is in a defensive pose.