Arnelliaceae is a monotypic family of liverworts belonging to the order Jungermanniales.

[2] The family only contains a single genus, Arnellia, which has only one known species, Arnellia fennica (Gottsche) Lindb..[3] which is known as the tundra liverwort.

[1] It is only found in the northern hemisphere of the world.

[1] The genus name of Arnellia is in honour of Hampus Wilhelm Arnell (2 August 1848 in Härnösand – 1932 in Uppsala), a Swedish bryologist.

[4]