Zeltnera namophila
Encyclopedia
Zeltnera namophila is a rare species of flowering plant in the gentian family
Gentianaceae
Gentianaceae are a family of flowering plants of 87 genera and over 1500 species. Flowers are actinomorphic and bisexual with fused sepals and petals. The stamens are attached to the inside of the petals and alternate with the corolla lobes. There is a glandular disk at the base of the gynoecium,...

 known by the common name spring-loving centaury. It is endemic to Ash Meadows
Ash Meadows National Wildlife Refuge
The Ash Meadows National Wildlife Refuge is a protected wildlife refuge, administered by the U.S. Fish and Wildlife Service, located west-northwest of Las Vegas, Nevada, in southern Nye County...

 in Nye County, Nevada
Nye County, Nevada
-National protected areas:* Ash Meadows National Wildlife Refuge* Death Valley National Park * Humboldt-Toiyabe National Forest * Spring Mountains National Recreation Area -Demographics:...

. It has been seen just over the border in California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

, but no occurrences are currently confirmed there. There are six main populations of the plant in the Ash Meadows area, including adjacent Bureau of Land Management
Bureau of Land Management
The Bureau of Land Management is an agency within the United States Department of the Interior which administers America's public lands, totaling approximately , or one-eighth of the landmass of the country. The BLM also manages of subsurface mineral estate underlying federal, state and private...

 territory, and the total global population is estimated to exceed four million plants. What seems like a large number is actually very limited in distribution and divided among the six populations, when the plant is thought to have been widespread throughout the area before the 1960s. These remaining populations are directly threatened by alterations in the hydrology
Hydrology
Hydrology is the study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability...

 of the area, as water is the limiting factor
Limiting factor
A limiting factor or limiting resource is a factor that controls a process, such as organism growth or species population, size, or distribution. The availability of food, predation pressure, or availability of shelter are examples of factors that could be limiting for an organism...

 for the species. This and other rare plants, including many Ash Meadows endemics, are declining there because the water table
Water table
The water table is the level at which the submarine pressure is far from atmospheric pressure. It may be conveniently visualized as the 'surface' of the subsurface materials that are saturated with groundwater in a given vicinity. However, saturated conditions may extend above the water table as...

 is dropping due to groundwater
Groundwater
Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...

 pumping. This is a federally listed threatened species of the United States.

This is an annual herb producing a branching stem up to 45 centimeters tall. The plant blooms during the heat of summer, from July to September. The flower is roughly a centimeter wide with a deep pink corolla tinged yellow in the throat. The fruit is a capsule containing about 50 seeds, and each plant can produce many capsules. It is thought to be a ruderal species
Ruderal species
A ruderal species is a plant species that is first to colonize disturbed lands. The disturbance may be natural , or due to human influence – constructional , or agricultural .Ruderal species typically dominate the disturbed area...

, producing many tiny seeds that spread about and sprout up in disturbed habitat in a weedlike manner. The seeds probably also persist for a long time in the soil seed bank
Soil Seed Bank
The soil seed bank refers to the natural storage of seeds, often dormant, within the soil of most ecosystems. The study of soil seed banks started in 1859 when Charles Darwin observed the emergence of seedlings using soil samples from the bottom of a lake. The first scientific paper on the subject...

.

The plant grows in moist and wet soils in the Ash Meadows wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....

s. The soil has a high clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...

 content and a high pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

, with salts remaining as water is evaporated in the desert air. The plant occurs in meadow
Meadow
A meadow is a field vegetated primarily by grass and other non-woody plants . The term is from Old English mædwe. In agriculture a meadow is grassland which is not grazed by domestic livestock but rather allowed to grow unchecked in order to make hay...

s of saltgrass (Distichlis spicata) and next to stream
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...

s, springs
Spring (hydrosphere)
A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...

, and seeps
Seep (hydrology)
A Seep is a moist or wet place where water, usually groundwater, reaches the earth's surface from an underground aquifer.-Description:Seeps are usually not of sufficient volume to be flowing beyond their above-ground location. They are part of the limnology-geomorphology system...

. Other plants in the area include Ash Meadows gumplant
Grindelia fraxino-pratensis
Grindelia fraxino-pratensis is a species of flowering plant in the daisy family known by the common name Ash Meadows gumplant, or Ash Meadows gumweed.-Distribution:...

 (Grindelia fraxino-pratensis), Emory baccharis
Baccharis emoryi
Baccharis emoryi is a species of baccharis known by the common name Emory's baccharis. It is native to the southwestern United States and northern Mexico, where it grows in sandy, moist habitat such as riverbanks. This is a shrub producing erect, branching stems approaching four meters in maximum...

 (Baccharis emoryi), and Tecopa bird's beak (Cordylanthus tecopensis).

This plant would probably be plentiful in pristine conditions, considering its having once been widespread and its ability to grow like a weed in many kinds of local moist habitat. The continuing loss of the natural water regime in the area, however, has limited it, but to what extent is not certain. Other threats and potential threats include trampling by mustangs
Mustang (horse)
A Mustang is a free-roaming horse of the North American west that first descended from horses brought to the Americas by the Spanish. Mustangs are often referred to as wild horses, but there is intense debate over terminology...

, cattle
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...

 grazing
Grazing
Grazing generally describes a type of feeding, in which a herbivore feeds on plants , and also on other multicellular autotrophs...

, mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

 for clay minerals
Clay minerals
Clay minerals are hydrous aluminium phyllosilicates, sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths, and other cations. Clays have structures similar to the micas and therefore form flat hexagonal sheets. Clay minerals are common weathering products and low...

 such as bentonite
Bentonite
Bentonite is an absorbent aluminium phyllosilicate, essentially impure clay consisting mostly of montmorillonite. There are different types of bentonite, each named after the respective dominant element, such as potassium , sodium , calcium , and aluminum . Experts debate a number of nomenclatorial...

, sepiolite
Sepiolite
Sepiolite is a clay mineral, a complex magnesium silicate, a typical formula for which is Mg4Si6O152·6H2O. It can be present in fibrous, fine-particulate, and solid forms....

, and saponite
Saponite
Saponite is a trioctahedral mineral of the smectite group. Its chemical formula is Ca0.2532·n. It is soluble in sulfuric acid. It was first described in 1840 by von Svanberg. Varieties of saponite are griffithite, bowlingite and sobotkite.It is soft, massive, and plastic, and exists in veins and...

, and introduced plant species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...

 such as yellow starthistle (Centaurea solstitialis) and saltcedar
Tamarix ramosissima
Tamarix ramosissima, commonly known as Saltcedar, is a deciduous arching shrub with reddish stems and feathery, pale green foliage.-Description:...

(Tamarix ramosissima). So far, refuge workers have kept these invasive plants to a manageable level.

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