How Many Body Parts Do Spiders Have?

Many people confuse spiders with insects due to their small size and bug-like appearance. While spiders might have similarities with insects, they are actually arachnids, which most noticeably differ in their amount of legs, the arachnids' eight legs compared to insects' six. This is not the only difference however, as spiders have their own array of unique body parts.

Significance

To be as broad as possible a spider has two body parts: the front breast called the cephalothorax, the back abdomen called the opisthosoma. However, there are other parts located within the main parts that help to define a spider.

Cephalothorax

This front main part consists of the head fused with breast plate. The eyes (six or eight) are located on the top, front of the head with the jaws located underneath the eyes. Also, all of the legs and the feelers (palps) are attached to cephalothrax.

Abdomen

This back main part contains all the vital organs, including the lungs and the heart. The spinner is located at the bottom end of the abdomen, allowing the spider to spin its silk thread.

Legs

The defining features of the spider are the its legs. Each leg, starting from the body and in descending order, has a femur, patella, tibia, metatarsus, tarsus and claw.

Palps

The palps, also called feelers, are located besides the jaws and help the spider shuffle food into the mouth. On the males, the palps have bulbs on the end that are used during mating.

Jaws

The business end of the spider, venom-injecting spikes are located at the end of the two muscular jaws. Most spiders have venom, the most venomous being the black widow and funnel web, but not all spiders are venomous.

References

• www.xs4all.nl
• University of Wisconsin - Green Bay