Arenaria norvegica

Arenaria norvegica
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Core eudicots
Order:	Caryophyllales
Family:	Caryophyllaceae
Genus:	Arenaria
Species:	A. norvegica
Binomial name
Arenaria norvegica Gunnerus

Arenaria norvegica, also known as Arctic, English or Norwegian sandwort, is a low growing plant in the pink family, Caryophyllaceae, found in northwest Europe. The chromosome number is 2n=80. There are two recognised subspecies.^[1]

Description

A. norvegica is a much branched, low-growing plant growing up to six centimetres tall. The midrib of the leaves is indistinct and the margins glabrous only in the lower third which distinguishes it from the rather similar Arenaria ciliata.^[1]

Arenaria norvegica subsp. anglica

A. norvegica subsp. anglica is an annual or biennial herb with few non-flowering shoots. The leaves are opposite, narrowly ovate or elliptic. The flowers are eleven to twenty-three millimetres in diameter, have five white petals and three styles.^[1] The plant flowers from May to October.^[2]

Arenaria norvegica subsp. norvegica

A. norvegica subsp. norvegica is a perennial herb with many non-flowering shoots. The leaves are obovate and the white flowers about ten centimetres across with five petals and three to five styles.^[1]

Distribution

Both subspecies are uncommon and localised.
A. norvegica subsp. anglica is restricted to limestone regions in the Yorkshire Dales in the United Kingdom.^[1]
A. norvegica subsp. norvegica is found in west and northwest Scotland, the Shetland Isles, western Ireland, and Scandinavia ^[3] and Iceland.^[4]

Habitat

Arenaria norvegica subsp. anglica favours thin peaty soils in cracks, depressions or hollows on limestone rock. It is also found growing in moist calcareous flushes and in gritty soil at the edge of tracks. It typically grows among small sedges, fescue grass and other members of the pearlwort and sandwort genera. It is classified as a vulnerable endemic species in the vascular plant British Red Data Book.^[2]

Arenaria norvegica subsp. norvegica is found on sandy and gravelly substrates ^[4] and is also restricted to limestone.^[3]

References

1. ^ ^{a b c d e} Flora of NW Europe
2. ^ ^{a b} Species Action Plan
3. ^ ^{a b} Michael Foley
4. ^ ^{a b} Plants of Iceland