Barychelidae, also known as brushed trapdoor spiders, is a spider family with about 300 species in 42 genera. Most spiders in this family build trapdoor burrows. For example, the 20 millimetres (0.79 in) long Sipalolasma builds its burrow in rotted wood, with a hinged trapdoor at each end. The 10 millimetres (0.39 in) long Idioctis builds its burrow approximately 5 centimetres (2.0 in) deep, just below the high tide level, sealing the opening with a thin trapdoor.

Some species avoid flooding by plugging their burrows, while others can avoid drowning by trapping air bubbles within the hairs covering their bodies. Some members of this group have a rake on the front surface of their chelicerae used for compacting burrow walls. These spiders can run up glass like tarantulas, and some can stridulate, though it isn't audible to humans.

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