Arnellia fennica

Arnellia fennica
Phylum: Marchantiophyta
Family: Arnelliaceae
Genus: Arnellia
Common NameTundra Liverwort
Quick & Dirty IDOpposite Leaves on Limestone
© petit_bonnier
iNaturalist
© petit_bonnier
iNaturalist
© petit_bonnier
iNaturalist

Distinguishing Features

Known from montane calcareous cliff shelves, where it can be found growing in bryophyte mats, A. fennica is a rarely seen species with light green, oppositely-arranged simple leaves on small, reclined shoots that grow to about 1 cm long and up to 1 mm wide. Hand lens inspection shows the small triangular underleaf and lateral leaves that are widely ellipsoidal and fused at their base when looked at on the upper surface of the stem. Some bryologists see blueish hues in this plant,

Similar species

A number of leafy liverwort genera (eg. Solenostoma, Jungermannia) have unlobed lateral leaves that can give off the appearance of being arranged oppositely, but close inspection of the leaf bases shows that they are arranged alternately. Of these genera, only species of Nardia and Odontoschisma have underleaves as in Arnellia fennica, but neither of those genera have their lateral leaves fused at their base along the upper surface of the stem.

Habitat

Associated species

Distribution Map

Relevant Literature