Wikijunior:Bugs/Jumping Spider

What does it look like?
Many Jumping Spiders are ¼ to ½ inch long. Some are 3/8 to 1 inch long. The cephalothorax (head and midsection) is shaped like a rectangle. In hot tropical regions they have bright colors and markings. Some have shiny scales to attract females. They have furry bodies and short hairy legs. Hairs sense movement of prey or predators. There are 2 claws on the tip of each leg. Sometimes there is a tuft of hair on each foot for climbing on slippery surfaces. Jumping Spiders have 8 eyes, including 2 really large eyes in the front. Young Jumping Spiders look like small versions of adults. They have different colors and markings.

Male Dimorphic Jumping Spiders have 2 different forms. One has clusters of black hair. The other has red, white, and black markings. Metaphid Jumping Spiders have spots, bands, and stripes. They are brown to yellow in color. Thick hair makes their legs look gray. Ant-mimic Jumping Spiders have a thick plate on the back and constrictions (narrow places) like ants. They are reddish-brown with white spots on each side of the abdomen. Daring Jumping Spider males are black with light cross-bands. They have either gray or white spots on the abdomen. Their chelicerae (jaws) are metallic green. The young often have pale, yellow or orange markings.

Where does it live?
Dimorphic Jumping Spiders live in meadows on leaves and flowers. They are found from New England to Georgia, and in the Midwest. Metaphid Jumping Spiders are found throughout North America. They live in woods, meadows, and tall grasses. They make homes on leaves and tree bark.

Ant-mimic Jumping Spiders are found from Quebec, Canada to Florida, and west to Texas and Nebraska. They live in meadows and woods, on soil and leaves. Daring Jumping Spiders are found from the Atlantic coast to the Rocky Mountains. They live on tree trunks, fallen limbs, and ground litter in the woods. They are common in gardens and houses.

One species of Jumping Spiders lives high in Asia’s Himalayan Mountains. Its scientific name means “standing above everything.”

What does it eat?
Jumping Spiders are daytime hunters. They eat small insects and spiders. They do not spin webs. They make a long silk dragline as they pounce on victims from above. If they miss they climb back up the dragline and try again. They have strong back legs to leap and catch flying insects.

Daring Jumping Spiders eat insects. They often hunt on window sills and curtains inside houses. Ant-mimic Jumping Spiders eat ants and small insects. The Green Jumping Spider of Australia eats small frogs.

How does it defend itself?
Jumping Spiders spin shelter webs for protection in winter. They make shelters under stones or leaves. Some hide in plain sight. They look like debris or bird droppings on a leaf, so predators ignore them. Some look like ants or scorpions to avoid being eaten. They have sharp eyesight to spot predators. They can run forward, backward, or sideways to avoid capture. They can jump to get far away from danger. They can leap forty times their body length. When they sense danger, they use their silk drag line to climb up and escape.

Their small eyes cannot see clearly, but they can detect motion in all directions. Their 2 large eyes work together to make clear images.

What stages of metamorphosis does it go through?
Spiders undergo simple or incomplete metamorphosis (change). They become adults in only three stages—egg, nymph (spiderling), adult. There is no “resting” stage before they become adults.

Jumping Spider males hop, dance, and show off their bright colors to attract a mate. Females spin a silk sac for the eggs. They hide the egg sac in leaves, bark, or crevices. Females guard their eggs for a few weeks. Inside the egg sac, spiderlings are blind, and unable to eat until they get bigger. When they are big enough, they chew a hole in the egg sac and float away on a silk string. They eat and molt until they mature. It takes 3 months to grow into an adult.

Metaphid Jumping Spiders make a cocoon for their eggs. They attach it to twigs and stay close while the spiderlings grow. Ant-mimic Jumping Spiders leave their egg sacs under stones and in crevices.

What special behavior does it exhibit?
Jumping Spiders are excellent hunters with very sharp eyesight. Two large eyes face forward. They work together to make one image (binocular vision). Unlike most spiders, Jumping Spiders can see colors.

Males wave their feelers to attract females. If a female approaches too quickly, the male backs away.

An Ant-mimic Jumping Spider will touch its front legs to an ant’s antennae. The ant does not recognize it as a predator and is captured.

They are curious. Instead of running away from people, they may sit and stare at them. Sometimes they jump into a person’s hand to get food. They can be trained to jump from finger to finger on a person’s hand.

Jumping Spiders will sometimes stick a dead insect on a leaf to lure prey.

The Australian Fringed Jumping Spider uses tricks to catch prey. It taps its legs or plucks web strands to make small vibrations. When the other spider comes out to investigate, it becomes the meal.

How does this bug affect people?
Jumping Spiders are mostly beneficial as they eat insect pests. They are especially helpful to rice farmers because they eat insects that destroy rice crops.

Jumping Spiders are not dangerous. They only bite in self-defense. Some people may have an allergic reaction to the venom. Though the venom usually does not harm us, and only leaves a small red dot