Mygalomorphae

Mygalomorphae is a suborder of spiders characterized by fangs that move vertically and the presence of four book lungs. These spiders are typically large, ground-dwelling, and nocturnal, constructing silk-lined burrows or chambers. They feed on small animals like insects, frogs, or mice. Mygalomorphs are considered primitive spiders and include well-known groups such as tarantulas and trapdoor spiders. They are distinguished by their two pairs of book lungs, downward-pointing chelicerae with venomous fangs, and one or two pairs of spinnerets.12