The Tetrablemmidae are a spider family with 126 described species in 29 genera that occur throughout the world tropics. They are sometimes called armored spiders.
The family Pacullidae was incorporated into this family in 1981, but in 2016 was restored as a separate family with four genera by Wheeler et al. in a large phylogenetic study.
Most tetrablemmids have been collected from litter and soil, including soil in epiphytes; some live in caves. Some cave species, but also some soil inhabitants, show typical adaptations of cave spiders, such as loss of eyes and weak sclerotization.
Spiders in the genus Paculla are four to five times larger than other tetrablemmids. The genus Tetrablemma features only four eyes, a trait only shared with most species of the not closely related Caponiidae.