Crab spiders are no active hunters. They make more use of the camouflage techniques than other spiders. They do not make a web but catch their prey with their front legs. The color of the spider is adapted to the hunting terrain they use and is mostly extravagant. They remain unmoved until the prey arrives and catches it. With a poisonous bite (not dangerous to humans) they kill their prey and suck it dry. They can be found on flowers or leaves of plants. Often the crab spider remains for days, even weeks at the same spot. The front two legs, that are often larger and stronger than the other six, are held sideways, ready to catch the prey immediately. Because they sit on easily spotted places they are also easy to catch by the predators. When they spot a possible enemy they move quickly at the other site of the flower or leave. Their eyesight is excellent developed as can be seen on the pictures. They have normally two big front eyes. 
Crab spiders are easy recognizable if you tease them. They widen their legs and move side ways like a crab. Their size is between 4 - 10 mm. 
The females usually stand guard with their egg sacs. The egg sacs are fastened to the vegetation and are usually flat.