Crab Spider

Found across North America and some parts of Europe, this is one of the most common spiders in the world. It is sometimes called a flower or goldenrod spider. It prefers to sit on flowers such as daisies and goldenrods and will change color to match the flower, from white to yellow. It is named after a crab because its body is shortened and rounded like a crabs.

Females are twice as large as males, growing up to 9 mm. Females are yellow or white with slight markings. Males are darker – red to reddish brown, and have a white spot near their eyes. An adult female’s main activity is to find food – she is a voracious hunter. She must build up enough body mass if she wants to have babies, and only large prey, like bumble bees, give her enough nutrition. A male’s main activity is to find females. He may even eat nectar sometimes if he can’t find enough prey. Females build nests for their eggs by folding leaves together. After mating, the female lays up to 350 eggs in mid-late summer. She will protect her eggs for nearly a month until they hatch. She may continue to feed them insects for a while after they are born.

Young spiderlings molt several times before becoming adults. They usually overwinter in the 3^rd to 6^th instar (molt stage). Scientists don’t think that any adults survive the winter, so only the young are left in the spring to start building up body weight and finding a mate. They believe that, if a spiderling doesn’t get big enough in one summer, it may overwinter again as an instar, before emerging the next spring to continue on its journey to adulthood.

The jaws of Misumena vitia are small, but they contain venom. It can attack and kill invertebrates larger than itself by holding its prey while it injects venom to paralyze them. It eats grasshoppers, flies and bees, amongst other invertebrates. Humans are not affected by the venom of crab spiders.

This species of spider, along with many other crab spiders, doesn’t spin a web. It spends its life in the sanctuary of a flower – camouflaged from predators – awaiting prey to happen by. Or, occasionally searching from flower to flower for more food or a mate.