Pallaviciniites

{{Short description|Species of liverwort}}

{{Speciesbox

| fossil_range = Frasnian

| parent_authority = Schuster 1966 (Hueber, 1961)

| genus = Pallaviciniites

| species = devonicus

| authority = Schuster 1966 (Hueber, 1961)

| synonyms = {{species list

| Hepaticites | Hueber 1961}}

}}

The lowermost Upper Devonian fossil Pallaviciniites was for a time the oldest known liverwort until Metzgeriothallus was recovered from earlier Devonian strata.{{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 had a central axis, and bifurcated at its tips; similar fossils have been found in younger strata through to the Pleistocene.{{cite book

| url = https://books.google.com/books?id=jEtVg4jTmq0C&q=Pallaviciniites&pg=PA1

| title = Topics in bryology

| isbn = 978-81-7023-811-9

| author1 = Chopra, R. N

| year = 1998| publisher = Allied Publishers

}} With the exception of its elongated axial conducting (non-vascular) cells, the thallus was a single cell thick.{{Cite journal | last1 = Banks | first1 = H. | title = The oldest vascular land plants: A note of caution | journal = Review of Palaeobotany and Palynology | volume = 20 | pages = 13–69 | year = 1975 | issue = 1–2 | doi = 10.1016/0034-6667(75)90004-4 | bibcode = 1975RPaPa..20...13B }} It had a serrated margin.{{Cite journal | last1 = Hueber | first1 = F. M. | title = Hepaticites devonicus, a New Fossil Liverwort from the Devonian of New York | jstor = 2394879 | journal = Annals of the Missouri Botanical Garden | volume = 48 | issue = 2 | pages = 125–131 | year = 1961 | doi = 10.2307/2394879}}

Prior to its discovery, the oldest known liverworts dated to the Lower Carboniferous.