Cypripedioideae is a

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

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. Orchids are cosmopolitan plants that are found in almost every habitat on Eart ...

s commonly known as lady's slipper orchids, lady slipper orchids or slipper orchids. Cypripedioideae includes the

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

Cypripedium ''Cypripedium'' is a genus of 58 species and nothospecies of hardy Orchidaceae, orchids; it is one of five genera that together compose the subfamily of lady's slipper orchids (Cypripedioideae). They are widespread across much of the Northern He ...

, Mexipedium, Paphiopedilum, Phragmipedium'' and '' Selenipedium''. They are characterised by the slipper-shaped pouches (modified labella) of the

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s – the pouch traps insects so they are forced to climb up past the staminode, behind which they collect or deposit pollinia, thus fertilizing the flower. There are approximately 165 species in the subfamily.

Description

All representatives of the Cypripedioideae are perennial, herbaceous plants. The fleshy roots sometimes possess a veil. The leaves are arranged spirally or in two rows, the shoot is slender or compressed. In the bud, the leaves are rolled and the leaf blade is plikat (folded) or the leaves are folded in the bud, smooth and leathery. There is no dividing tissue between leaf and shoot. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

of the Cypripedioideae are terminal and mostly unbranched. The flowers are spiral or in two lines on the shoot, they are resupinated. The petals are in two threefold circles, with mostly two petals of the outer circle are completely fused. The labellum forms a sac-like structure. The ovary is under constant and one-chambered or three-chambered. Two fertile stamens, a staminode and

style Style, or styles may refer to: Film and television * ''Style'' (2001 film), a Hindi film starring Sharman Joshi, Riya Sen, Sahil Khan and Shilpi Mudgal * ''Style'' (2002 film), a Tamil drama film * ''Style'' (2004 film), a Burmese film * '' ...

are fused into a complex structure. The stylus is short and thick, the stigma is large and convex, the central lobe of the stigma is larger than the two lateral ones. The two lateral stamens are fertile, the pollen grains are glued together to form a paste or formed into connected pollinia in some '' Phragmipedium'' species. The middle, barren stamen is shield-shaped widened. The fruits are mostly capsule fruits, with ''Selenipedium'' they are berry-like. They contain numerous flattened seeds, about a millimeter long and 0.1 millimeters wide. In contrast, the seeds of ''Selenipedium'' are lens-shaped and have a hard seed coat. Chromosome numbers vary within the subfamily over a wide range from 2n=20 in ''

'' to 26 to 44 chromosomes in '' Paphiopedilum''. The chromosomes are quite large. The species in this subfamily form trap flowers in which insect access to the saclike lip from the front is quite easy. The inside is designed in such a way that the insects climb out of the flower past the stigma and the stamens and thereby pollinate the flower.

Distribution

The species in the subfamily Cypripedioideae are found in northern South America and Central America (''Mexipedium'', ''Phragmipedium'', ''Selenipedium''), circumboreal in North America, Europe, Africa (Algeria) and in northern Asia (''Cypripedium'') as well as in subtropical and tropical Southeast Asia (''Paphiopedilum''). They do not occur in Australia and Africa. The spread could have started from a center of origin in Central America.

Taxonomy

Unlike most other orchids, slipper orchids have two fertile

anther The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s — they are "diandrous". For that reason, experts have debated whether this

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

should be classified within the orchid family (

Orchidaceae Orchids are plants that belong to the family (biology), family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Orchids are cosmopolitan distribution, cosmopolitan plants that ...

), or whether they should compose a separate family altogether called Cypripediaceae. Around the year 2000,

molecular phylogenetics Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

and DNA sampling have come to play an increasingly important role in classification. This has led to the conclusion that recognition of a distinct family Cypripediaceae would be inappropriate. The subfamily Cypripedioideae is

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

and consists of five genera: :* ''

'', found across much of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

, as well as in parts of

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

(one species),

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

(only in

Algeria Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Alger ...

has been discovered in 2019) and

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

. The state flower of

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

is the showy lady's slipper ('' Cypripedium reginae''); the pink lady's slipper ('' Cypripedium acaule'') is the official flower of the

Canadian province Canada has ten provinces and three territories that are sub-national administrative divisions under the jurisdiction of the Constitution of Canada, Canadian Constitution. In the 1867 Canadian Confederation, three provinces of British North Amer ...

Prince Edward Island Prince Edward Island is an island Provinces and territories of Canada, province of Canada. While it is the smallest province by land area and population, it is the most densely populated. The island has several nicknames: "Garden of the Gulf", ...

. :* '' Mexipedium'', a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus, consisting of a single species that was found in a single locality in Oaxaca, Mexico. :* '' Paphiopedilum'', found in the tropical forests of

southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

reaching as far north as southern

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

. ''Paphiopedilum'' is quite easy to cultivate and therefore is popular among orchid enthusiasts. In fact, over-collection of this genus has been so extensive that many species are now sub-viable in their natural habitats. :* '' Phragmipedium'', found across northern South and Central America, is also easy to cultivate as it requires lower

temperature Temperature is a physical quantity that quantitatively expresses the attribute of hotness or coldness. Temperature is measurement, measured with a thermometer. It reflects the average kinetic energy of the vibrating and colliding atoms making ...

s than ''Paphiopedilum'', eliminating the need for a

greenhouse A greenhouse is a structure that is designed to regulate the temperature and humidity of the environment inside. There are different types of greenhouses, but they all have large areas covered with transparent materials that let sunlight pass an ...

in many areas. :* '' Selenipedium'', found in Central and

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

Intergeneric hybrids

Hybrids between the genera in this subfamily are placed in the following nothogenera:Alphabetical One-Table List of Genera and Intergeneric Hybrids
Royal Horticultural Society, 2017. * × ''Cyphiopedilum'' (''Cphd.'') = ''Cypripedium'' × ''Paphiopedilum'' * × ''Cyphragmipedium'' (''Cgd.'') = ''Cypripedium'' × ''Phragmipedium'' * × ''Phragmipaphium'' (''Phrphm.'') = ''Paphiopedilum'' × ''Phragmipedium'' Hybrids with genera outside of the subfamily are not known as of 2017.

References

External links

* *
The Slipper Orchid Alliance

SlipperOrchids.info
{{Taxonbar, from=Q132226 Asparagales subfamilies Provincial symbols of Prince Edward Island