The Neotropical praying mantises of the genus Liturgusa (Saussure) are comprehensively treated after receiving little or no taxonomic attention after their original descriptions. All species are strictly associated with tree bark habitats and appear flattened and highly camouflage while also being adept runners that will actively hide by fleeing to the opposite side of a tree trunk if disturbed; some species have even been observed fluttering to the forest floor and playing dead. This work includes redescriptions of the genus and all previously described species, descriptions of three new genera and 19 new species, identification of four new synonyms, complete bibliographies for each species, a key to identify males and females, locality data for all examined specimens, measurement ranges for all species, diagnostic illustrations, and high resolution images of types and representative specimens. This work triples the known diversity of Neotropical bark mantises and documents their natural history as well as geographic distribution, which includes central Mexico south to Bolivia and east to southern Brazil.