Porella is a large, common, and widespread genus of liverworts in order Porellales. It is a member of the family Porellaceae within that order.

There were 84 species recognized in 2016, most of them from East Asia. World Flora Online accepts 125 species, and GBIF accepts 150 species (as of 4 July 2023).

The genus has a wide cosmopolitan distribution in temperate areas, where it is commonly found growing attached to the bark of trees. Members of the genus have lobed leaves with a large upper lobe and small lower lobe.

Species Porella arboris-vitae, Porella bolanderi, Porella cordeana, Porella navicularis, Porella pinnata, Porella platyphylla and Porella roellii, were all found in Montana, USA.

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