Metzgeriothallus

{{Short description|Extinct genus of liverworts}}

{{Automatic taxobox

| fossil_range = {{fossil range|Givetian|Lower Mississippian}}

| taxon = Metzgeriothallus

| authority = Walton, 1928

| subdivision_ranks = Species

| subdivision = {{species list

| M. metzgerioides|Walton, 1928 (type)

| M. sharonae| VanAller Hernick et al., 2008}}

}}

Metzgeriothallus sharonae is the oldest known liverwort fossil, dating to the Middle Devonian.{{Cite journal | last1 = Hernick | first1 = L. | last2 = Landing | first2 = E. | last3 = Bartowski | first3 = K. | title = Earth's oldest liverworts—Metzgeriothallus sharonae sp. nov. from the Middle Devonian (Givetian) of eastern New York, USA | journal = Review of Palaeobotany and Palynology | volume = 148 | pages = 154–162 | year = 2008 | issue = 2–4 | doi = 10.1016/j.revpalbo.2007.09.002 | bibcode = 2008RPaPa.148..154H }} It is a simple, thalloid organism. M. metzgerioides is known from more fragmentary material dating to the Carboniferous of Scotland.