Bogumil Stachowiak
Bogumil Stachowiak voted up PJ Stein's answer

There are at least five different respiratory systems in spiders, depending on taxonomic group and whom you’re talking to. 1) A single pair of booklungs, as with the cellar or daddylongleg spiders, Pholcidae. 2) Two pair of booklungs, suborder Mesothelae, and all or most of infraorder Mygalomorphae (including tarantulas). 3) A pair of booklungs and … Read more

Bogumil Stachowiak
Bogumil Stachowiak voted up PJ Stein's answer

There are at least five different respiratory systems in spiders, depending on taxonomic group and whom you’re talking to. 1) A single pair of booklungs, as with the cellar or daddylongleg spiders, Pholcidae. 2) Two pair of booklungs, suborder Mesothelae, and all or most of infraorder Mygalomorphae (including tarantulas). 3) A pair of booklungs and … Read more