Hormidium
Encyclopedia
The taxonomic concept "Hormidium" has been published numerous times with the same meaning but with different taxonomic ranks: as a genus
by Bentham & Hooker, as a subgenus
of Epidendrum
by Reichenbach, and as a section
of Epidendrum by Lindley. To simplify the nomenclature, the historical concept will be treated herein as if it were a genus: although Kew states that the generic epithet is a synonym for Prosthechea
, some of the species attributed to Hormidium are now classified in Encyclia
, Epidendrum
, Homalopetalum
, and Lepanthes
.
adnate to the column
, with pseudobulbous
stems, and with sessile flowers. Reichenbach concluded that the subgenus "Hormidium" was superfluous, explaining "Tota sectio superflua ad Aulizea pertinet!" and included only four species.
Bentham & Hooker went into somewhat more detail to distinguish Hormidium from the other pseudobulbous species with (at least partially) adnate labella, and specifically mentioned only four species, two of which are still retained in Epidendrum, the one which is now placed in Homalopetalum, and the one which is now placed in Lepanthes. Because the genus Encyclia features non-adnate labella, and because the genus Prosthechea features labella which are only partially adnate (and therefore do not quite meet Lindley's criteria for Hormidium), Bentham's & Hooker's description is useful:
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
by Bentham & Hooker, as a subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...
of Epidendrum
Epidendrum
Epidendrum , abbreviated Epi in horticultural trade, is a large neotropical genus of the orchid family. With more than 1,100 species, some authors describe it as a mega-genus. The genus name refers to its epiphytic growth habit...
by Reichenbach, and as a section
Section (botany)
In botany, a section is a taxonomic rank below the genus, but above the species. The subgenus, if present, is higher than the section, and the rank of series, if present, is below the section. Sections are typically used to help organise very large genera, which may have hundreds of species...
of Epidendrum by Lindley. To simplify the nomenclature, the historical concept will be treated herein as if it were a genus: although Kew states that the generic epithet is a synonym for Prosthechea
Prosthechea
Prosthechea is a genus in the orchid family . The name is derived from the Greek word prostheke , referring to the appendage on the back of the column....
, some of the species attributed to Hormidium are now classified in Encyclia
Encyclia
Encyclia is a genus of orchids. The genus name comes from Greek enkykleomai , referring to the lateral lobes of the lip which encircle the column. The abbreviation in the horticultural trade is E....
, Epidendrum
Epidendrum
Epidendrum , abbreviated Epi in horticultural trade, is a large neotropical genus of the orchid family. With more than 1,100 species, some authors describe it as a mega-genus. The genus name refers to its epiphytic growth habit...
, Homalopetalum
Homalopetalum
Homalopetalum is a genus of flowering plants from the orchid family, Orchidaceae.- References :*Pridgeon, A.M., Cribb, P.J., Chase, M.A. & Rasmussen, F. eds. . Genera Orchidacearum 1. Oxford Univ. Press....
, and Lepanthes
Lepanthes
Lepanthes is a large genus of orchids with about 800–1000 species, distributed in the Antilles and from Mexico through Bolivia . The genus is abbreviated in horticultural trade as Lths...
.
Description
As originally envisioned by Lindley, the section included those species of Epidendrum with the flower lipLabellum
Labellum is the Latin diminutive of labium, meaning lip. These are anatomical terms used descriptively in biology, for example in Entomology and botany.-Botany:...
adnate to the column
Column (botany)
The column, or technically the gynostemium, is a reproductive structure that can be found in several plant families: Aristolochiaceae, Orchidaceae, and Stylidiaceae....
, with pseudobulbous
Pseudobulb
The pseudobulb is a storage organ derived from the part of a stem between two leaf nodes.It applies to the orchid family , specifically certain groups of epiphytic orchids, and may be single or composed of several internodes with evergreen or deciduous leaves along its length.In some species, it is...
stems, and with sessile flowers. Reichenbach concluded that the subgenus "Hormidium" was superfluous, explaining "Tota sectio superflua ad Aulizea pertinet!" and included only four species.
Bentham & Hooker went into somewhat more detail to distinguish Hormidium from the other pseudobulbous species with (at least partially) adnate labella, and specifically mentioned only four species, two of which are still retained in Epidendrum, the one which is now placed in Homalopetalum, and the one which is now placed in Lepanthes. Because the genus Encyclia features non-adnate labella, and because the genus Prosthechea features labella which are only partially adnate (and therefore do not quite meet Lindley's criteria for Hormidium), Bentham's & Hooker's description is useful:
- The plant is a small epiphyteEpiphyteAn epiphyte is a plant that grows upon another plant non-parasitically or sometimes upon some other object , derives its moisture and nutrients from the air and rain and sometimes from debris accumulating around it, and is found in the temperate zone and in the...
. The pseudobulbs and rhizome are covered with membranaceous sheathes. The pseudobulb bears one or two small leathery or fleshy leaves. The flowers are small (or larger, in the case of Hormidium sophronitis), born on a short raceme. The floral bracts are small. The sepals are of equal lengths, partially closed or completely open, the dorsal sepal free at the rear and the lateral sepals adnate to the base of the column forming a small "ladle." The petals are similar to the sepals or very narrow. The labellum is adnate to the column to its apex with completely erect lamina, either trilobate or lacking any divisions. The column is short with a dilated margin. The clinandrium is short and truncated. The terminal, operculate, slightly kidney-shaped anther leans against the column and carries four pollinia. The flattened egg-shaped pollinia are distinct from each other.
Species & synonymy
According to Kew, the following species have been placed in the genus Hormidium, with the following accepted names:- H. almasii (Hoehne) Brieger (1960) = Prosthechea glumacea
- H. baculibulbum (Schltr.) Brieger (1960) = Prosthechea vespa
- H. boothianum (Lindl.) Brieger (1960) = Prosthechea boothiana
- H. caetense Bicalho (1972) = Prosthechea caetensis
- H. coriaceum Brieger (1960) = Prosthechea vespa
- H. faresianum Bicalho (1973) = Prosthechea faresiana
- H. faustum (Rchb.f. ex Cogn.) Brieger (1960) = Prosthechea fausta
- H. gilbertoi (GarayGarayGarai is a town and municipality located in the province of Biscay, in the autonomous community of Basque Country, northern Spain.-External links:*...
) P.Ortiz (1982) = Prosthechea gilbertoi - H. glumaceum (Lindl.) Brieger (1960) = Prosthechea glumacea
- H. hioramii AcunaAcuña-People:*Alex Acuña , Peruvian percussionist*Antonio Osorio de Acuña , Spanish bishop*Carlos Javier Acuña , Paraguayan football player*Clarence Acuña , Chilean footballer...
& RoígRoigRoig is a Catalan surname, it means red, may refer to:From father*Arturo Andrés Roig, Argentine philosopherFrom mother*Juan Ramón Epitié Dyowe Roig, footballer from Equatorial Guinea, born in Catalonia...
(1936) = Prosthechea pygmaea - H. humile (Cogn.) Schltr. (1920) = Prosthechea pygmaea
- H. leochilus (Rchb.f.) B.D.Jacks. (1893) = Homalopetalum leochilus
- H. miserum (Lindl.) Benth. & Hook.f. ex Hemsl. (1884) = Epidendrum miserum
- H. pseudopygmaeum Finet (1899) = Prosthechea pygmaea
- H. pulchellum (Sw.Olof SwartzOlof Peter Swartz was a Swedish botanist and taxonomist. He is best known for his taxonomic work and studies into pteridophytes...
) Benth. & Hook.f. ex B.D.Jacks. (1893) = Lepanthes pulchella - H. pygmaeum (Hook.) Benth. & Hook.f. ex Hemsl. (1884) = Prosthechea pygmaea
- H. racemiferum (DresslerDresslerDressler may refer to:* Anton Dressler , clarinetist* Conrad Dressler , sculptor and potter* Erich Dressler, luger* Gallus Dressler , composer and music theorist* Marie Dressler , actress...
) Withner & P.A.Harding (2004) = Prosthechea racemifera - H. rhynchophorum (A.Rich. & GaleottiHenri Guillaume GaleottiHenri Guillaume Galeotti was a French-Belgian botanist and geologist of Italian parentage who was born in Paris. He specialized in the study of the family Cactaceae....
) Withner & P.A.Harding (2004) = Prosthechea rhynchophora - H. serpensEpidendrum serpensEpidendrum serpens is a sympodial pseudobulbous orchid that grows among lichens on trees near the tree line at altidudes of 1.6-3.5 km in Peru and Ecuador, including the states of Azuay and Pichincha.-Description:...
(Lindl.) Benth. & Hook.f. (1883) = Epidendrum serpens - H. sessiliflorum (Edwall) PabstPabstPabst may refer to:*Pabst Brewing Company, brewing company once owned by Frederick Pabst*Pabst Blue Ribbon, a notable beer owned by the Pabst Brewing Company*Pabst Brewery Complex, the facility in Milwaukee, Wisconsin that was closed in 1997...
, Moutinho & A.V.Pinto (1981) = Prosthechea sessiliflora - H. sophronitisEpidendrum sophronitisEpidendrum sophronitis Linden & Rchb.f. is a small Epidendrum orchid that bears a superficial resemblance to a Sophronitis, as the generic epithet was used prior to the year 2000.-Description:...
(LindenJean Jules LindenJean Jules Linden , was a Belgian botanist and explorer, horticulturist and businessman, specialising in orchids, on which subject he wrote a number of books....
& Rchb.f.) Benth. & Hook.f. (1883) = Epidendrum sophronitis - H. tripterum (Brongn.) Cogn. (1898) = Prosthechea pygmaea
- H. uniflorum (Lindl.) Heynh.Gustav HeynholdGustav Heynhold was a German botanist.In 1841, he renamed Arabis thaliana as Arabidopsis thaliana Heynh. in honour of Johannes Thal.His author abbreviation is Heynh.-Works:...
(1841) = Prosthechea pygmaea - H. variegatum Brieger (1960) = Prosthechea vespa
- H. virensEncyclia diurnaEncyclia diurna is a species of orchid.-Synonyms:*Limodorum diurnum Jacq. *Cymbidium diurnum Sw.*Epidendrum diurnum Poir.*Cymbidium glandulosum Kunth*Epidendrum virens Lindl....
Brieger (1960) = Encyclia diurna - H. widgrenii (Lindl.) Brieger (1960) = Prosthechea widgrenii