''Corallorhiza odontorhiza'', common name fall coral-root or small-flowered coral-root, is a 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 ...

widespread across eastern and central United States, and reported also from

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

Quebec Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...

and

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

. In North America, it occurs in forested areas up to an elevation of 2800 m (9300 feet). ''Corallorhiza odontorhiza'' is a non-

photosynthetic Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in c ...

species, with no

chlorophyll Chlorophyll (also chlorophyl) is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words , ("pale green") and , ("leaf"). Chlorophyll allow plants to a ...

. Hence it relies on

fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

in the soil to supply it with nutrients. Stems are yellow to brown, bulbous at the base. There are no leaves. Flowers are typically reddish-purple with a white lip, the lip with small purple spots, though some plants are

cleistogamous Cleistogamy is a type of automatic self-pollination of certain plants that can propagate by using non-opening, self-pollinating flowers. Especially well known in peanuts, peas, and pansies, this behavior is most widespread in the grass family. How ...

with non-opening flowers. The plant flowers from August through October in the eastern US.Freudenstein, J. V. 1997. A monograph of ''Corallorhiza'' (Orchidaceae). Harvard Papers in Botany 1(10): 5–51.Hamer, F. 1988. Orchids of Central America. Selbyana 10(Suppl.): 1–430.

Infraspecific taxa

Three

infraspecific taxa In botany, an infraspecific name is the scientific name for any taxon below the rank of species, i.e. an infraspecific taxon or infraspecies. (A "taxon", plural "taxa", is a group of organisms to be given a particular name.) The scientific names ...

are recognized as of May 2014: *''Corallorhiza odontorhiza'' var. ''odontorhiza'' - Quebec, Ontario, eastern and central United States *''Corallorhiza odontorhiza'' var. ''pringlei'' (Greenm.) Freudenst. - Mexico, Central America, Ontario, eastern United States *''Corallorhiza odontorhiza'' var. ''pringlei'' f. ''radia'' Freudenst. - southern Mexico, Guatemala, El Salvador

''Corallorhiza odontorhiza var. odontorhiza''

The flowers of ''var. odontorhiza'' are

and either closed or only slightly open. Often one or two flowers in a raceme will be open slightly more than the others and a narrow lip (2.6-3.8mm long, 1.7-2.2mm wide) may be visible. Because flowers self-pollinate and no external pollinators are required first, the ovaries of this variation will start swelling soon after flowering.

''Corallorhiza odontorhiza var. pringlei f. pringlei''

Flowers of ''var. pringlei'' are

chasmogamous Chasmogamy, is a plant reproductive mechanism in which pollination occurs in chasmogamous flowers. Chasmogamous flowers are commonly showy with open petals encircling exposed reproductive parts. Chasmogamous stems from Greek for "open marriage", na ...

and will open up. Their upper two petals and upper sepal form a hood, with the two side sepals bending outwards. The lip is visible and wider than with ''var. odonthoriza'' - it is used by pollinators to land on.

''Corallorhiza odontorhiza var. pringlei f. radia''

This form of ''var. pringlei'' is only known from southern Mexico, Guatemala and El Salvador. It is completely cleistogamous and

peloric Floral symmetry describes whether, and how, a flower, in particular its perianth, can be divided into two or more identical or mirror-image parts. Uncommonly, flowers may have no axis of symmetry at all, typically because their parts are spirall ...

- that is unlike with ''var. odontorhiza'' the bottom-most petal does not form a lip but looks just like the other 5 petals/sepals. Since it is assumed that a peloric form of the orchid could develop anywhere as a spontaneous mutation it is only recognized as a

form Form is the shape, visual appearance, or configuration of an object. In a wider sense, the form is the way something happens. Form also refers to: *Form (document), a document (printed or electronic) with spaces in which to write or enter data ...

and not a full variation.

References

{{Taxonbar, from=Q15432276 Orchids of the United States Orchids of Canada Orchids of Mexico Orchids of Central America odontorhiza Plants described in 1805 Flora without expected TNC conservation status