The novel morphology of gemma in Marchantia pinnata Steph., an endemic species to east Asia, is reported for the first time. The outer shape of gemma is gourd-like with maximum width ca. 250 μm and length ca. 350 μm. The surface is not smooth due to the swelling of the cells. The margin of gemmae is never entire due to mammillose and with several papillae on marginal cells. The two apical notches have no mucilage hairs. These morphologies are widely different from those of a common species, M. polymorpha subsp. ruderalis with larger and nearly circular in outer shape, entire margin and mucilage hairs in notches. Morphological characters of gemmae might be useful for the identification of Marchantia species.

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