the hard, external body shell of arthropods. It is made of a stiff material called the cuticle, which has many layers. The cuticle is the building material of the entire body surface, the joint membranes, tendons, apodemes, sensory hairs, and even the lining of the respiratory and reproductive organs. Apart from those structural functions, the cut [..]

(pl: chelicerae) these are the mouthparts that are tipped with fangs; aka the jaws. In most species they open and close like a pair of salad tongs, while in others, like tarantulas and trap-door species, they move up and down in a stabbing motion. The fangs rest in a groove in the bottom of the chelicerae similar to blades in a pocket knife. Chelic [..]

 the hindmost section of the spider body, also called the opisthosoma. The heart, reproductive organs, respiratory organs, digestive tract, and silk spinning glands are all included inside the abdomen. This body segment is soft and expandable, unlike the rest of the spider’s hard exoskeleton.

 nearer to the front end; i.e. the eyes are anterior to the abdomen.

a member of the Class Arachnida. This includes spiders, ticks, mites, scorpions, and their kin. Spiders belong to the Order Araneae.

 one who studies the class Arachnida, which contains all the arachnids (spiders, scorpions, mites, ticks, opiliones, etc).

 one who studies the order Araneae, which contains only the spiders.

 also called “autospasy”, this is the act of a spider voluntarily amputating, or dropping off, its own leg(s) in response to a dangerous situation in order to help free itself. Dangerous situations include being grabbed or caught by something, maybe a predator, as well as having a limb get stuck during the process of molting. For example, spiders o [..]

 the spiders’ respiratory organs. These are usually situated on the underside of the abdomen, towards the front. They look like hairless patches of cuticle. Underneath those hairless covers, there are “stacks” of hemolymph-filled cuticle. Via diffusion, air passes in between the layers of those “stacks” and allows the gas exchange to take place. Li [..]

 the shield-like covering that protects the top of the cephalothorax.