Arctoa hyperborea

(Gunnerus ex Withering) Bruch & Schimper

Bryol. Europ.1: 157. 1846,

Synonyms: Cynodontium hyperboreum Dicranum hyperboreum
Basionyms: Bryum hyperboreum
Found in FNA Volume 27. Treatment on page 363. Mentioned on page 362.
Dicr Arctoa hyperborea 2007 02 20.jpeg
Plants in compact, dark green tufts. Stems 1–3(–5) cm. Leaves erect-spreading, lanceolate, subulate, 2–3 mm; costa 30–55 µm wide at base, short-excurrent, rough near tip; distal laminal cells mostly subquadrate (1–2:1), incrassate; basal laminal cells elongate, alar cells differentiated, quadrate or slightly enlarged. Seta 4–6(–8) mm. Capsule exserted, slightly curved, obscurely to distinctly ribbed when dry, annulus developed, separating; peristome large, not spreading outward when dry. Spores 18–30 µm.

Phenology: Capsules mature summer.
Habitat: Siliceous rock or soil
Elevation: high-alpine elevations


Greenland, Europe.


Arctoa hyperborea is a rare arctic-alpine moss found on rock ledges or crevices at high elevations. It is distinguished from other species of the genus by its short-excurrent costa, shorter seta (the length is highly variable), and peristome not spreading when dry.



Facts about "Arctoa hyperborea"
AuthorSteven G. Newmaster +
BasionymBryum hyperboreum +
Elevationhigh-alpine elevations +
HabitatSiliceous rock or soil +
IllustratorPatricia M. Eckel +
PhenologyCapsules mature summer. +
ReferenceNone +
SynonymCynodontium hyperboreum + and Dicranum hyperboreum +
Taxon nameArctoa hyperborea +
Taxon parentArctoa +
Taxon rankspecies +
VolumeVolume 27 +