Sagina is a genus of 20–30 species of flowering plant

Flowering plant

The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...

s in the family Caryophyllaceae

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...

. These are flowering herbs native to temperate regions of the Northern Hemisphere

Northern Hemisphere

The Northern Hemisphere is the half of a planet that is north of its equator—the word hemisphere literally means “half sphere”. It is also that half of the celestial sphere north of the celestial equator...

 extending south to tropical mountain

Mountain

Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...

 areas at high altitudes, reaching just south of the equator

Equator

An equator is the intersection of a sphere's surface with the plane perpendicular to the sphere's axis of rotation and containing the sphere's center of mass....

 in Africa

Africa

Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

. They are small annual

Annual plant

An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...

 or perennial

Perennial plant

A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...

 herbaceous

Herbaceous

A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...

 plants, erect or prostrate, growing to 5–15 cm tall or broad. The leaves

Leaf

A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

 are opposite, often in tight whorl-like clusters, simple linear, typically 5–20 mm long. The flower

Flower

A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...

s are solitary or in small cymes, with four or five green sepals and an equal number of white petals; the petal size relative to the sepal size is useful in species identification. The fruit

Fruit

In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...

 is a small capsule

Capsule (fruit)

In botany a capsule is a type of simple, dry fruit produced by many species of flowering plants. A capsule is a structure composed of two or more carpels that in most cases is dehiscent, i.e. at maturity, it splits apart to release the seeds within. A few capsules are indehiscent, for example...

 containing several seed

Seed

A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...

s.

Species:

Sagina abyssinica Sagina afroalpina Sagina apetala Sagina apetala Sagina apetala is a species of flowering plant in the pink family known by the common names annual pearlwort and dwarf pearlwort. It is native to Europe and it is known elsewhere as an introduced species, including parts of North America. It grows in many types of disturbed habitat, such as cracks... - Annual Pearlwort Sagina boydii - Boyd's Pearlwort Sagina brachysepala Sagina caespitosa Sagina decumbens Sagina decumbens Sagina decumbens is a species of flowering plant in the pink family known by the common names trailing pearlwort and western pearlwort. It is native to several areas of North America, where it can be found in many types of habitat. It is a small annual herb producing a threadlike green or purplish... - Trailing Pearlwort Sagina glabra Sagina japonica - Japanese Pearlwort Sagina maritima - Sea Pearlwort

Sagina maxima Sagina maxima Sagina maxima is a species of flowering plant in the pink family known by the common name stickystem pearlwort. It is native to the west coast of North America from Alaska to California, where it can be found in many types of sandy and rocky coastal habitat. It is a small, fleshy perennial herb... - Stickystem Pearlwort Sagina melitensis Sagina muscosa Sagina nivalis - Snow Pearlwort Sagina nodosa Sagina nodosa Sagina nodosa is a species in the genus Sagina, native to northern Europe. It is a low-growing plant up to 15 cm tall, with paired leaves up to 1 cm long. The flowers are 5–10 mm diameter, with five white petals.... - Knotted Pearlwort Sagina pilifera Sagina pilifera Sagina pilifera is a species of Sagina, native to the Mediterranean islands of Corsica and Sardinia, where it grows in mountains at altitudes of 1,000–2,700 m... Sagina procumbens Sagina procumbens Sagina procumbens is a species of flowering plant in the pink family known by the common name birdeye pearlwort. It can be found throughout the Northern Hemisphere and parts of South America. It is a common weed of many environments. It can be found in wild and disturbed habitat, especially moist... - Procumbent Pearlwort Sagina sabuletorum Sagina saginoides Sagina saginoides Sagina saginoides is a species of flowering plant in the pink family known by the common name arctic pearlwort. It has a Circumboreal distribution; it can be found throughout the northern latitudes of the Northern Hemisphere. It grows in subalpine and alpine climates and other mountainous habitat... - Alpine or Arctic Pearlwort Sagina subulata Sagina subulata Sagina subulata is a species of Sagina, native to Europe, from Iceland south to Spain, and east to southern Sweden and Romania... - Heath Pearlwort (syn. S. pilifera)

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