''Pleurothallis'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

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 floweri ...

s commonly called bonnet orchids. The genus name is derived from the Greek word , meaning "riblike branches". This refers to the rib-like stems of many species. The genus is often abbreviated as "Pths" in horticultural trade. This was a huge genus, which used to contain more than 1,200

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

- the second largest in the

Orchidaceae 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 flowerin ...

after '' Bulbophyllum''. In 2004, it decreased by more than half when many species were moved into new genera.

Distribution

''Pleurothallis'' is a completely

New World The term ''New World'' is often used to mean the majority of Earth's Western Hemisphere, specifically the Americas."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: Oxford University Press, p. ...

group, widespread across much of

Mexico Mexico (Spanish language, Spanish: México), officially the United Mexican States, is a List of sovereign states, country in the southern portion of North America. It is borders of Mexico, bordered to the north by the United States; to the so ...

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. ...

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sou ...

and the

West Indies The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Greate ...

.Kew World Checklist of Selected Plant Families, ''Pleurothallis''
/ref> Flora of North America lists one species in

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and ...

''(P. gelina)'' but this has now been transferred to a different genus, ''

Stelis ''Stelis'', or leach orchids, is a large genus of orchids, with perhaps 500 species. The generic name ''Stelis'' is the Greek word for 'mistletoe', referring to the epiphytic habit of these species. These mainly epiphytic (rarely lithophytic) p ...

''. The center of diversity of the genus is in the high

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

, especially in the chain of cloud forests in

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the ...

. ''Pleurothallis'' grows in dry or wet, tropical or temperate climates.

Description

As a group they show a huge range in vegetative form, terrestrial or epiphytic, and can be found as tall cane-like plants a metre or so high, clumped or trailing, pendent or climbing, erect or creeping, tufted and tiny, delicate moss-like species that can grow on the thinnest of twigs. But they have one common denominator: they all have two pollinia. They have reduced their pseudobulbs and instead, some species have thick succulent leaves. Their flowers are among the most diverse and unusual, although often very small, and specialize in using tiny

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three pa ...

s such as gnats or small wasps for

pollination Pollination is the transfer of pollen from an Stamen, anther of a plant to the stigma (botany), stigma of a plant, later enabling fertilisation and the production of seeds, most often by an animal or by Anemophily, wind. Pollinating agents can ...

Taxonomy

To bring some order in this extremely diverse genus, 29 subgenera and 25 sections had been created. Much of this work has been done by Dr. C. Luer of the

Missouri Botanical Garden The Missouri Botanical Garden is a botanical garden located at 4344 Shaw Boulevard in St. Louis, Missouri. It is also known informally as Shaw's Garden for founder and philanthropist Henry Shaw. Its herbarium, with more than 6.6 million ...

. A new analysis, based on DNA testing, confirmed on the whole the classification of the subtribe Pleurothallidinae, with however ''Pleurothallis'' as the main difference. New genetic insight broke up this huge genus and made it more consistent with the principles of

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gr ...

genera and

evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

ary relationships. Several times before, a splitting up has been attempted, but there were always too many intermediate forms. In 2004 the genera '' Acianthera'', '' Ancipitia'', '' Antilla'', '' Apoda-prorepentia'', '' Areldia'', '' Atopoglossum'', '' Brenesia'', '' Crocodeilanthe'' were created, incorporating a large number of former ''Pleurothallis'' species. The subgenera ''Pleurothallis'' and ''Specklinia'' are becoming separate genera, and the subgenus ''Acuminatae'' might become the proposed genus ''

Anathallis ''Anathallis'' is a genus of orchids, comprising about 97 species native to Mexico, Central America, South America and the West Indies The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribb ...

''. Other allied genera include ''

Dracula ''Dracula'' is a novel by Bram Stoker, published in 1897. As an epistolary novel, the narrative is related through letters, diary entries, and newspaper articles. It has no single protagonist, but opens with solicitor Jonathan Harker taki ...

'', '' Masdevallia'', ''

Restrepia ''Restrepia'', abbreviated Rstp in horticultural trade, is a small genus of 50orchids in the orchid family (Orchidaceae), closely related to ''Pleurothallis''. Named in honor of Don Jose Restrepo, it tends to be more showy than most other Pleur ...

'', and ''

''.Analysis of the DNA-Based Reclassification of the Pleurothallidinae
/ref>

Species

Pleurothallis crossota (Orchidaceae) (29426272544)

, Kew's

Plants of the World Online Plants of the World Online (POWO) is an online database published by the Royal Botanic Gardens, Kew. It was launched in March 2017 with the ultimate aim being "to enable users to access information on all the world's known seed-bearing plants by ...

listed around 540 species in the genus. Selected species include:

References

* Luer, Carlyle; 1986 - Icones Pleurothallidinarum III: Systematics of ''Pleurothallis'' (Orchidaceae); Missouri Botanical Garden Press. * {{Taxonbar, from=Q29979 Pleurothallidinae genera