Maybe She Will...Maybe She Won't

A big female crab spider about the size of a small quarter dollar.

Crab spiders or, more precisely, misusenoides formosipes, are found on flowers where they wait to ambush typical pollinators.
Popular thought says the spiders change color to match the flower they're on.  Fun!  This one was found  in a neighbors yard and the color match was so precise the camera had to define where the flower started and the spider ended.  
White crab spiders will sit in white Datura blossoms...yellow ones hide in...well...yellow blossoms.  
Two theories exist.  One is that when these spiders travel to a new location, a different flower of a different color, the spider's color will change in about a week.  The other theory postulates that they simply assume the color of the flower they were hatched on.

The result is probably academic...a female that changes color is fairly common.

Crab spiders make use of camouflage more than other spiders.  The color of the spider is adapted to the hunting terrain.

Because they sit in easily spotted places they become vulnerable prey.  When they spot a possible enemy they move quickly to the other side of their location or leave. 

Crab spiders are recognizable if you tease them. They spread their legs and move side ways...like a crab. 

Although crab spiders are fairly common, finding one might take some patience because they are often well camouflaged. If you want to find a crab/flower spider, try to think like a spider: Where would you sit if you wanted your prey to come to you?