The lowermost Upper Devonian fossil Pallaviciniites was for a time the oldest known liverwort until Metzgeriothallus was recovered from earlier Devonian strata.

[2] It had a central axis, and bifurcated at its tips; similar fossils have been found in younger strata through to the Pleistocene.

[3] With the exception of its elongated axial conducting (non-vascular) cells, the thallus was a single cell thick.

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

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