''Spiranthes delitescens'' is a rare species of

orchid Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering ...

known by the common names reclusive lady's tresses, Canelo Hills lady's tresses, and Madrean lady's tresses. It is native to

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

in the United States, where there are only four occurrences. It is threatened by the loss and degradation of its habitat. It is a federally listed

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...

of the United States. This orchid was first collected in 1968 and described to science as a species in 1990.McClaran, M. P. and P. C. Sundt. (1992)
Population dynamics of the rare orchid, ''Spiranthes delitescens''.
''The Southwestern Naturalist'' 37(3) 299-303. It produces an erect stem up to 50 centimeters tall.''Spiranthes delitescens''.
Center for Plant Conservation. The narrow leaves are arranged around the lower part of the stem and are up to 18 centimeters long. The

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. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is a spiraling spike of flowers. The stem in the inflorescence is covered in glandular hairs. Each flower has curving white, cream, or yellow-tinged petals nearly one centimeter in length. Blooming occurs in July and August.''Spiranthes delitescens''.
Flora of North America. This and other orchid species depend on

mycorrhiza A mycorrhiza (from Greek μύκης ', "fungus", and ῥίζα ', "root"; pl. mycorrhizae, mycorrhiza or mycorrhizas) is a symbiotic association between a fungus and a plant. The term mycorrhiza refers to the role of the fungus in the plant ...

e, soil-dwelling fungi species, to assist with

germination Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, fer ...

, and for nutrition.''Spiranthes delitescens''.
Arizona Game and Fish Department. This plant grows in cienegas, a

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...

habitat type in an otherwise dry region in the

southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...

, at an

elevation The elevation of a geographic location is its height above or below a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational surface (see Geodetic datum § Vert ...

around 1525 meters (5000 feet).''Spiranthes delitescens''.
The Nature Conservancy. Other plants in the habitat include a variety of

grass Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns an ...

es,

sedges The Cyperaceae are a family of graminoid (grass-like), monocotyledonous flowering plants known as sedges. The family is large, with some 5,500 known species described in about 90 genera, the largest being the "true sedges" genus ''Carex'' wit ...

, spikerushes, cat-tails, and horse-tails. Cienegas are kept seasonally wet by springs. Two of the cienegas occupied by the orchid are the O'Donnell and Turkey Creek Cienegas, located about 40 kilometers southeast of

Tucson, Arizona , "(at the) base of the black ill , nicknames = "The Old Pueblo", "Optics Valley", "America's biggest small town" , image_map = , mapsize = 260px , map_caption = Interactive map ...

. The O'Donnell Cienega is owned by

The Nature Conservancy The Nature Conservancy (TNC) is a global environmental organization headquartered in Arlington, Virginia. it works via affiliates or branches in 79 countries and territories, as well as across every state in the US. Founded in 1951, The Natu ...

, and a permanent caretaker lives at the site. The other two occurrences are Babocomari Cienega and Sheehy Spring nearby. The orchid may also exist south of the border in

Sonora, Mexico Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Federal Entities of Mexico. The state is divided into 72 municipalities; the ...

. It is difficult to estimate the orchid's abundance, because it spends most of its time in a dormant, or vegetative state, remaining hidden in the dense surrounding vegetation with few identifiable aboveground parts.USFWS
Determination of endangered status for three wetland species found in southern Arizona and northern Sonora, Mexico.
''Federal Register'' January 6, 1997. The main threat to the species is the loss and degradation of its habitat, caused in part by the

invasion An invasion is a military offensive in which large numbers of combatants of one geopolitical entity aggressively enter territory owned by another such entity, generally with the objective of either: conquering; liberating or re-establishing con ...

of non-native plant species and the overgrowth of native plants. The worst invasive species is

Johnson grass Johnson grass or Johnsongrass, ''Sorghum halepense'', is a plant in the grass family, Poaceae, native to Asia and northern Africa. The plant has been introduced to all continents except Antarctica, and most larger islands and archipelagos. It re ...

(''Sorghum halepense''). The orchid grows naturally next to various species of horse-tail and other marsh plants, and when these plants become too dense the orchid cannot penetrate the layers of vegetation. Horse-tails also outcompete the orchid. It is likely that

fire suppression Wildfire suppression is a range of firefighting tactics used to suppress wildfires. Firefighting efforts in wild land areas require different techniques, equipment, and training from the more familiar structure fire fighting found in populated a ...

is a threat, as fires naturally thin competing vegetation.

Grazing In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to roam around and consume wild vegetations in order to convert the otherwise indigestible (by human gut) cellulose within grass and other ...

of cattle and other livestock is a threat, though grazing has been eliminated in the most sensitive cienega sites in most locations. Changes in the

hydrology Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is calle ...

of these wetland sites is a threat to the habitat, which is still recovering from draining operations initiated over a century ago. Pumping of

groundwater Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidate ...

reduces available water in the habitat. The specific name ''delitescens'' is derived from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''delitescere'' meaning "to hide", "to withdraw" or "to take refuge".

References

External links

''Spiranthes delitescens''.
Arizona Native Plant Society Fact Sheet. {{Taxonbar, from=Q7577787 delitescens Endemic orchids of the United States Flora of Arizona Plants described in 1990