They're ambush predators.

Here you are, a bee, touching down on a flower and little do you know there's a patient and persistent crab spider lying in wait. 

Sometimes they're camouflaged, matching the color of a blossom, like a yellow crab spider on a gold coin, or a pinkish-white crab spider on sedum. 

But there was no missing this white crab spider on a Mexican sunflower (Tithonia) last weekend. It stood out like a snowy owl perched on a crate of crimson pomegranates.

Crab spiders belong to the family Thomisidae and are often called "flower crab spiders." They're not web weavers or jumping spiders. They're ambush specialists that trap  unsuspecting prey.

If you're wondering why some honey bees, leafcutter bees, blue orchard bees or sweat bees don't go home at night, the crab spider is one of the reasons.