California Crab Spiders

The crab spider belongs to the Order Araneae and Family Thomisidae, and there are several species found in California as well as much of the U.S. With flat bodies and long front legs, these arachnids appear to move the way that crabs do. However, although crab spiders resemble crabs, they are true spiders. They often are found resting on flowers where they wait for their prey. Crab spiders prey on insects such as bees and butterflies.

Crab spiders can mimic the color of the flowers on which they wait. The coloration helps them blend in with flowers to surprise prey and are thus also known as flower spiders. When prey approaches, they bite and paralyze it through the use of venom, and all food sources are liquefied by digestive enzymes prior to consumption.

Crab spiders live for approximately one year and undergo a relatively simple life cycle. Females lay their eggs on plants or flowers and protect the eggs from harm. When egg sacs hatch, young crab spiders emerge. These young spiders appear similar to adults, although their bodies are significantly smaller. Crab spiders undergo a series of molts before becoming adults.