Stellaria longipes
Encyclopedia
Stellaria longipes is a species of flowering plant in the pink family
known by the common name longstalk starwort. It has a circumpolar
distribution, occurring throughout the northernmost latitudes of the Northern Hemisphere. It grows in a wide variety of habitat types, including tundra
and taiga
and many areas farther south with subalpine
and alpine climate
s. It is extremely variable in morphology
, its form depending on both genetic makeup and environmental conditions. It has a widely varying number of chromosome
s. In general, it is a rhizomatous
perennial herb forming mats or clumps, or growing erect. The stems may be short and simple or with sprawling and highly branched. The linear to lance-shaped leaves are usually 1 to 4 centimeters long and are oppositely arranged in pairs. The inflorescence
bears one or more flowers, each on a a short pedicel
. The flower has five pointed green sepal
s each a few millimeters long. There are five white petals each divided into two lobes, sometimes shallowly, but often so deeply there appear to be two petals. The plant is gynodioecious
, with some flowers having functional male and female reproductive parts and others being only female.
There are two subtaxa. The rarer of the two, ssp. arenicola, is limited to the sand dunes
adjacent to Lake Athabasca
in central Canada.
Caryophyllaceae
The Caryophyllaceae, commonly called the pink family or carnation family, is a family of flowering plants. It is included in the dicotyledon order Caryophyllales in the APG III system, alongside 33 other families, including Amaranthaceae, Cactaceae and Polygonaceae...
known by the common name longstalk starwort. It has a circumpolar
Arctic Circle
The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth. For Epoch 2011, it is the parallel of latitude that runs north of the Equator....
distribution, occurring throughout the northernmost latitudes of the Northern Hemisphere. It grows in a wide variety of habitat types, including tundra
Tundra
In physical geography, tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands," "treeless mountain tract." There are three types of tundra: Arctic tundra, alpine...
and taiga
Taiga
Taiga , also known as the boreal forest, is a biome characterized by coniferous forests.Taiga is the world's largest terrestrial biome. In North America it covers most of inland Canada and Alaska as well as parts of the extreme northern continental United States and is known as the Northwoods...
and many areas farther south with subalpine
Subalpine
The subalpine zone is the biotic zone immediately below tree line around the world. Species that occur in this zone depend on the location of the zone on the Earth, for example, Snow Gum in Australia, or Subalpine Larch, Mountain Hemlock and Subalpine Fir in western North America.Trees in the...
and alpine climate
Alpine climate
Alpine climate is the average weather for a region above the tree line. This climate is also referred to as mountain climate or highland climate....
s. It is extremely variable in morphology
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
, its form depending on both genetic makeup and environmental conditions. It has a widely varying number of chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
s. In general, it is a rhizomatous
Rhizome
In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...
perennial herb forming mats or clumps, or growing erect. The stems may be short and simple or with sprawling and highly branched. The linear to lance-shaped leaves are usually 1 to 4 centimeters long and are oppositely arranged in pairs. The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
bears one or more flowers, each on a a short pedicel
Pedicel (botany)
A pedicel is a stem that attaches single flowers to the main stem of the inflorescence. It is the branches or stalks that hold each flower in an inflorescence that contains more than one flower....
. The flower has five pointed green sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s each a few millimeters long. There are five white petals each divided into two lobes, sometimes shallowly, but often so deeply there appear to be two petals. The plant is gynodioecious
Gynodioecy
Gynodioecy is a dimorphic breeding system in which male sterile individuals coexist with hermaphroditic individuals in populations. Although there is a claim that gynodioecy exists among the animal population, most recorded works done on this subject has been done using plant species...
, with some flowers having functional male and female reproductive parts and others being only female.
There are two subtaxa. The rarer of the two, ssp. arenicola, is limited to the sand dunes
Athabasca Sand Dunes Provincial Park
Athabasca Sand Dunes Provincial Park is a unique geophysical land feature in the boreal shield ecosystem of the province of Saskatchewan. It first came to attention that it should be a protected area in 1969, finally becoming the Athabasca Sand Dunes Provincial Wilderness Park on August 24, 1992. ...
adjacent to Lake Athabasca
Lake Athabasca
Lake Athabasca is located in the northwest corner of Saskatchewan and the northeast corner of Alberta between 58° and 60° N.-History:The name in the Dene language originally referred only to the large delta formed by the confluence the Athabasca River at the southwest corner of the lake...
in central Canada.