Stelis

{{Short description|Genus of orchids}} {{Italic title}} {{For|the genus of bees|Stelis (bee)}} {{Use dmy dates|date=September 2025}} {{Automatic taxobox | name = Leach orchid | image = Stelis argentata.jpg | image_caption = Silvery stelis (''Stelis argentata'') | display_parents = 3 | taxon = Stelis | authority = Sw., 1799 | synonyms_ref = <ref name="WCSP"/> | synonyms = *''Humboltia'' Ruiz & Pav. *''Physosiphon'' Lindl. *''Dialissa'' Lindl. *''Crocodeilanthe'' Rchb.f. & Warsz. *''Pseudostelis'' Schltr. *''Physothallis'' Garay *''Steliopsis'' Brieger in F.R.R.Schlechter *''Apatostelis'' Garay *''Salpistele'' Dressler *''Condylago'' Luer *''Mystacorchis'' Szlach. & Marg. *''Dracontia'' (Luer) Luer *''Elongatia'' (Luer) Luer *''Unciferia'' (Luer) Luer *''Loddigesia'' Luer *''Lomax'' Luer *''Effusiella'' Luer *''Niphantha'' Luer }}

'''''Stelis''''', or '''leach orchids''', are a large genus of orchids, with 1339 accepted species.<ref>{{Cite web |title=Stelis Sw. {{!}} Plants of the World Online {{!}} Kew Science |url=https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:326634-2#children |access-date=2025-05-26 |website=Plants of the World Online |language=en}}</ref> The generic name ''Stelis'' is the Greek word for 'mistletoe', referring to the epiphytic habit of these species. These mainly epiphytic (rarely lithophytic) plants are widely distributed throughout much of South America, Central America, Mexico, the West Indies and Florida.<ref name="WCSP">[http://apps.kew.org/wcsp/namedetail.do?name_id=196288 Kew World Checklist of Selected Plant Families]</ref> ''Stelis'' is abbreviated '''''Ste.''''' in the horticultural trade.<ref>{{cite web|url=https://www.rhs.org.uk/plants/pdfs/plant-registration-forms/orchid-name-abbreviations-list.pdf|title=Alphabetical list of standard abbreviations of all generic names occurring in current use in orchid hybrid registration as at 31st December 2007|publisher=Royal Horticultural Society}}</ref>

Many of the older species were named by Lindley, Ruiz & Pavon and Reichenbach, while many of the recent species were named by Carlyle A. Luer. An orchid of the genus ''Stelis'' was probably the first American orchid ever to be brought to Europe. An herbarium specimen was depicted in 1591 in Tabernaemontanus' herbal book.

thumb|right|250px|'Indian mistletoe' first depiction of a ''Stelis'' orchid pub 1625 in Herbal Book of Johannes Theodorus Tabernaemontanus

==Description== A single oblanceolate leaf develops from narrow, leathery outgrowths from a creeping stem.<ref>{{Cite web |url=https://www.earth.com/earthpedia/plant/en/stelis/ |title=Archived copy |access-date=2020-02-12 |archive-date=2020-09-15 |archive-url=https://web.archive.org/web/20200915065649/https://www.earth.com/earthpedia/plant/en/stelis/ |url-status=dead}}</ref>

Most species grow long, dense racemes of small to minute flower in diverse shades of white. Other colors are rare. These flowers are photosensitive, only opening in the sunlight. Some close completely at night.

The three symmetrically rounded sepals generally form a triangle with a small central structure, made up of the column, small petals and small lip, though slight variation to this theme does occur.

This genus is not common in cultivation.

==Taxonomy== Cladistic research (by A. Pridgeon, R. Solano and M. Chase) has shown that the genus ''Stelis'' is monophyletic. But the distinction with several ''Pleurothallis'' subgenera is blurred (see Reference).

They are closely related to the massive genus ''Pleurothallis'' and ''Masdevallia''. Although vegetatively the species show much variety, the flowers show a basic uniformity and are very similar throughout. '''''Apatostelis''''' Garay, '''''Dialissa''''' Lindl., '''''Humboldtia''''' Ruiz & Pav. and '''''Steliopsis''''' Brieger are generally included into ''Stelis''.

==History== The genus ''Stelis'' was discovered with Charles Plumier, a French priest and botanist who was sent by Louis XIV, King of France, to study the flora of the Antilles in around 1690. He collected numerous species in Dominica (Caribbean island) and other islands, and published his findings in a catalogue called ''Nova Plantarum Americanarum Genera'' in 1703. Later on, Nikolaus von Jacquin, a Dutch botanist who collected extensively in the Caribbean, published his findings in two separate works. In 1760, he published the first one called ''Enumeratio Systematica Plantarum quas in Insulis Caribeis,'' where he described the same plant as Plumier´s polynomial (''Epidendrum ophioglossoides''). In 1763, he published a more detailed second work called ''Selectarum Stirpium Americanarum Historia''. Here, Jacquin describes a plant of his own herbarium with the same name (''E. ophioglossoides'')<ref name=":1">{{Cite book |title=ORCHIDACEAE STELIS SWARTZ |last=Duque |first=Oscar |year=2008 |publisher=Universidad de Antioquia |isbn=978-9587141078}}</ref>

Afterwards, on the "Expedición Botánica Española" (Spanish Botanic Expedition) sent by King Carlos III to study the flora of Peru and Chile, Hipolito Ruiz and Joseph Pavon complete results established 11 small plants of a new genus which they named ''Humboltia'' in honor of the renowned German explorer and naturalist Alexander Von Humboldt. In 1799, Olof Swartz, a Swedish botanist, studied the genus proposed by Ruiz and Pavon and found that it had been already used by Vahl to designate a Leguminosae. Because of this, he proposed the name ''Stelis'' in replacement of ''Humboltia.'' The species ''Epidendrum ophioglossoides'' was later moved to the genus ''Stelis'' by Swarz, and it is now the type species of the genus.<ref name=":1" />

==Species== {{Unreferenced section|date=August 2022}} {{Main|List of Stelis species}}

Select species of ''Stelis'' include: *''Stelis alata'' Lindl. – winged stelis *''Stelis argentata'' Lindl. – silvery stelis *''Stelis aviceps'' Lindl. – bird head stelis *''Stelis barbata'' Rolfe – bearded stelis *''Stelis bidentata'' Schltr – two-toothed stelis *''Stelis ciliaris'' Lindl. – hairy stelis *''Stelis crescentiicola'' Schltr – Crescentia living stelis *''Stelis dalstroemii'' Luer *''Stelis flexuosa'' – flexuous stelis *''Stelis gemma'' – gem stelis *''Stelis glomerosa'' – ball stelis *''Stelis guatemalensis'' – Guatemalan stelis *''Stelis intermedia'' Poepp. & Endl. – in-between stelis *''Stelis leinigii'' – Leinig's stelis *''Stelis megantha'' – giant anther stelis *''Stelis palmeiraensis'' – Palmeira stelis *''Stelis pauciflora'' Lindl. *''Stelis papaquerensis'' Rchb.f. *''Stelis perpusilliflora'' – West Indian leach orchid *''Stelis porschiana'' – Porsch's stelis *''Stelis purpurea'' – purple stelis *''Stelis pygmaea'' – pygmy leach orchid *''Stelis triangulisepala'' – triangular sepal stelis

==References== {{Reflist}} * Dr. C. Luer - Icones Pleurothallidinarum XXIV: A first century of new species of ''Stelis'' of Ecuador. Part 1 (2002); {{ISBN|1-930723-15-6}} * Dr. C. Luer - Icones Pleurothallidinarum XXVI: ''Pleurothallis'' subgenus ''Acianthera'' and three allied subgenera; A Second Century of New Species of ''Stelis'' of Ecuador; ''Epibator'', ''Ophidion'', ''Zootrophion'' (2004); {{ISBN|1-930723-29-6}} * [http://www.amjbot.org/cgi/content/full/88/12/2286 Phylogenetic relationships in Pleurothallidinae] {{Webarchive|url=https://web.archive.org/web/20220711073311/http://www.amjbot.org/cgi/content/full/88/12/2286 |date=2022-07-11 }}.

==External links== * {{Commons-inline|Stelis (Orchidaceae)|''Stelis''}} * {{Wikispecies-inline|Stelis (Orchidaceae)|''Stelis''}}

Category:Stelis Category:Epiphytic orchids Category:Pleurothallidinae genera Category:Orchids of Central America Category:Orchids of North America Category:Orchids of South America Category:Orchids of Florida Category:Orchids of Mexico Category:Flora of the Caribbean Category:Taxa named by Olof Swartz Category:Flora without expected TNC conservation status