Book Lungs True Spiders

A book lung is a type of respiration organ used for atmospheric gas exchange that is present in many arachnids such as scorpions and spiders each of these organs is located inside an open ventral abdominal air filled cavity atrium and connects with the surroundings through a small opening for the purpose of respiration.

Book lungs true spiders. Haemolymph is similar to blood for a spider. Book lungs are a series of very thin leaf like structures like the pages in a book. As in the trachea the book lungs exchange oxygen and carbon dioxide through diffusion.

The spider s normal movement provides all of the necessary energy to push air in and out. Some have a pair of book lungs others have several pairs. The book lungs are saturated in light blue haemolymph.

Spiders have developed several different respiratory anatomies based either on book lungs or on tracheae. Spiders such as tarantulas in the mygalomorphae infra order and mesothelae suborder have two pairs of book lungs. The book lungs located inside the arachnid are made up of several thin membranes somewhere between 10 and 80 depending the species.

Mesothele and mygalomorph spiders have two pairs of book lungs filled with haemolymph where openings on the ventral surface of the abdomen allow air to enter and oxygen to diffuse in and carbon dioxide to diffuse out. The inside of each leaf is filled with blood and the outside is exposed to air.