PROFILPELAJAR.COM

Androsace americana
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Ericales
Family:	Primulaceae
Genus:	Androsace
Species:	A. americana
Binomial name
	Androsace americana; Wendelbo
Synonyms
	Douglasia arctica Hook. ; Douglasia nivalis var. glabra Duby ; Gregoria arctica (Hook.) House ; Primula linearis Kuntze ;

Androsace americana, synonym Douglasia arctica, known as the Mackenzie River dwarf primrose,^[2] is a species of flowering plant in the primrose family, Primulaceae. It is native to subarctic North America (Alaska, the Northwest Territories and Yukon).^[1]

Taxonomy

The species was first described by William Jackson Hooker in 1838 as Douglasia arctica.^[3] Molecular phylogenetic studies showed that the genus Douglasia is nested within Androsace.^[4]^[5] The name "Androsace artica" was published in 1826 for a different species (now regarded as a synonym of Androsace ochotensis), so the replacement name Androsace americana, published by Per Wendelbo in 1961,^[6] is used instead.

Description

Androsace americana are relatively small, usually found as mats growing up to about 2 inches tall.^[7] They have a single, short stem that protrude from each rosette of leaves.^[8] Leaves are smooth and closely packed, forming rosettes of leaves that reach an average of 3/8 inches long.^[8] Androsace americana typically flowers in june.^[7] Pink petals are most commonly observed, but white petals can occur with older, more mature plants.^[7] Petals are deeply lobed and fuse at the bottom to form the flower.^[8] Scapes are generally 2 mm in early anthesis, but range from 2–4 cm in fruits, and are typically glandular and hairy, but can sometimes be hairless.^[7]

Phenology

Androsace americana has been described as both a perennial^[7] and as a long-lived cushion. It has been suggested that as a cushion, the plant's canopy functions as a buffer for temperature variation, allowing for elevated temperature inside the plant.^[9]

Distribution and habitat

Androsace americana, like other Androsace species, are found in cold climates ^[9] Androsace americana is native to Northern America as well as Subarctic America, and it is typically found in Alaska, Northwest Territories, Yukon, and Canada. It prefers to grow on rocky and mossy slopes.^[8]

References

^ ^a ^b ^c "Androsace americana (A.Gray) Wendelbo", Plants of the World Online, Royal Botanic Gardens, Kew, retrieved 2020-07-05
^ Kelso, Sylvia, "Douglasia arctica", in Flora of North America Editorial Committee (ed.), Flora of North America (online), eFloras.org, retrieved 2020-07-05
^ "Douglasia arctica Hook.", International Plant Names Index (IPNI), Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Botanic Gardens, retrieved 2019-05-09
^ Trift, I.; Anderberg, A.A. & Källersjö, M. (2002), "The monophyly of Primula (Primulaceae) evaluated by analysis of sequences from the chloroplast gene rbcL.", Systematic Botany, 27 (2): 396–407, JSTOR 3093879
^ Schneeweiss, Gerald M.; Schönswetter, Peter; Kelso, Sylvia & Niklfeld, Harald (2004), "Complex biogeographic patterns in Androsace (Primulaceae) and related genera: evidence from phylogenetic analyses of nuclear internal transcribed spacer and plastid trnL-F sequences", Systematic Biology, 53 (6): 856–876, doi:10.1080/10635150490522566, JSTOR 4135374, PMID 15764556
^ "Androsace americana Wendelbo", International Plant Names Index (IPNI), Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Botanic Gardens, retrieved 2019-05-09
^ ^a ^b ^c ^d ^e "Taxon Page". www.efloras.org. Retrieved 2021-11-24.
^ ^a ^b ^c ^d "Douglasia arctica". www.cdhs.us. Retrieved 2021-11-24.
^ ^a ^b Boucher, Florian C.; Thuiller, Wilfried; Roquet, Cristina; Douzet, Rolland; Aubert, Serge; Alvarez, Nadir; Lavergne, Sébastien (2012). "Reconstructing the Origins of High-Alpine Niches and Cushion Life Form in the Genus Androsace S.l. (primulaceae)". Evolution. 66 (4): 1255–1268. doi:10.1111/j.1558-5646.2011.01483.x. ISSN 1558-5646. PMC 3999638. PMID 22486702.