Parts of a Spider

Spiders share many similar characteristics with other arachnids. These physical characteristics include the presence of eight jointed legs, chelicerae, simple eyes, pedipalps, and exoskeleton, as well as the absence of antennae and wings.

Their body, unlike that of an insect, is divided into the following visible segments:

  1. Cephalothorax
  2. Abdomen

What are the Parts

1. Cephalothorax

Also known as prosoma, the cephalothorax is a fused body part containing the head and thorax, which bear the legs, eyes, and mouthparts. A cuticular plate (called a carapace) covers the cephalothorax, much like the shell of a crab.

Eyes

Spiders typically have multiple eyes (up to eight) set in two rows at the front of their carapace. The size of their eyes and the arrangement can vary depending on the species.

Mouthparts

They have a pair of large jaws with piercing claws or fangs, called the chelicerae. These chelicerae are hollow and consist of venom glands, and they are used for injecting venom into prey.

Pedipalps

Pedipalps or palps are a pair of appendages located in front of a spider’s legs. These help it in handling and tasting food and sensing touch. Male spiders use them for transferring sperms to their female partners during mating.

Legs

Spiders usually have eight legs, which they use for walking. The legs are segmented into the coxa, femur, patella, trochanter, metatarsus, tarsus, and tibia. Each of the tarsi has claws, which can vary in size and number. The sensitive hair-like structures on their legs help detect sounds, vibrations, air currents, and scent.

2. Abdomen

The abdomen or opisthosoma is covered with two hard cuticular plates, called the epigastric plates, which help protect the book lungs of a spider. The thin, flexible pedicel separates the abdomen from the cephalothorax, allowing for the movement of its abdomen during mating and silk spinning.

Gonopore

These are the genital openings from which the sperms or eggs are released. In female spiders, another plaque-like genital opening exists, called the epigynum.

Spinnerets

The abdomen of spiders has one to four pairs of movable appendages called spinnerets, which are used for producing silk. These spinnerets are located at the end of the small rounded anal projection.

FAQs

Q: How many legs does a spider have?

All spiders, unlike insects, possess eight legs.

Q: Can spiders regrow legs?

If a spider loses one or more legs, it can regrow them as long as it has one more molt remaining in its life cycle. It usually takes more than molts until the newly grown legs match the original in size and color.

Q: What do baby spiders look like?

Baby spiders or spiderlings have an appearance similar to their parents except that they are considerably smaller.