Petalophyllaceae is a family of liverworts in the orderFossombroniales. Most species are thallose; that is, the plant is not differentiated into root, stem, and leaf. The thallus is typically small and bears lamellae on its dorsal surface that give it a ruffled, leafy appearance.[2][3]
^ abCrandall-Stotler, B.J., Stotler, R.E., and Long, D.G. 2009. Phylogeny and classification of the Marchantiophyta. Edinburgh Journal of Botany, vo. 66, no. 1, p. 155-198.