Trapdoor spiders are medium-sized mygalomorph spiders that construct burrows with a cork-like trapdoor made of soil, vegetation and silk. Some similar species are also called trapdoor spiders, such as the Liphistiidae

Liphistiidae

The spider family Liphistiidae comprises 5 genera and 85 species from Southeast Asia, China, and Japan. They are among the most basal living spiders, belonging to the suborder Mesothelae...

, Barychelidae

Barychelidae

The Brushed trapdoor spiders are a spider family with about 300 species in 44 general. This family is the only family in superfamily Barycheloidea....

, Cyrtaucheniidae and some Idiopidae

Idiopidae

Idiopidae Idiopidae Idiopidae (superfamily Idiopoidea are a mygalomorph spider family. They have a large body that often looks rather like a tarantula.-Description:In some species the males have a spur on their legs, which they will show if provoked....

 and Nemesiidae

Nemesiidae

The Nemesiidae are a spider family of the infraorder Mygalomorphae, and the only member of the superfamily Nemesioidea. They were formerly considered part of the Dipluridae family.-Description:...

. Some Conothele species do not build a burrow, but construct a silken tube with trap-door in bark crevices.
The trapdoor is difficult to see when it is closed because the plant and soil materials effectively camouflage it.