Holcoglossum
Holcoglossum kimballianum
The genus Holcoglossum belongs to the orchid family (Orchidaceae) and originates from the tropical to subtropical climates of Asia. The genus now comprises about 15 known species and was erected in 1919 by the German botanist Rudolf Schlechter based on Saccolabium quasipinifolium Hayata as a monotypic genus.
Description
All species of this genus are perennial epitaxial or Lithophytes and are characterized by a short monopodial shoot axis with terete or triangular in cross-section sheets from. The top forms by highly folded sheet edges from a gutter. The leaves are tapered and are not notched at the tip. The root tips of living roots show in all species of the genus on a reddish tint, further some species have rotgeflecktes foliage. The flowering stem arises laterally from the stem axis, forming two or more flowers of these are widely spaced and form a cluster or panicle. The flowers are white and wide open. The lip is three-lobed. The lateral lobes are erect and are dotted adaxial. The middle part is spread over a large area and is parallel to the gynostemium. The lip is shaped so as to allow a potential pollinators depressing the middle lip. The flowers have an elongated spur that is severely regressed in the subgenus Brachycentron. The gynostemium has a large scar area. The stamen contains two separate porate pollinia. That the pollinia and the adhesive disk ( Viscidium ) connecting stalks ( stipes ) bends in the middle when removing from the rostellum. The rostellum is deeply incised. The number of chromosomes is in almost all types of 2n = 38 Holcoglossum tsii has in the diploid set of chromosomes 76 chromosomes ( 2n = 76).
Dissemination
The distribution of the genus extends across southwest China, Laos, Vietnam, Thailand and Malaysia. However, most of the species comes from the province of Yunnan in southwest China. Holcoglossum quasipinifolium is the only species endemic to Taiwan. The species living at higher altitudes between 1200 m and 3300 m and thus prefer a cool to cold habitat.
Culture
The small species of this genus should be grown in small pots or baskets, as well as tied up on cork boards. Grows in cool, moist forests, they need cool temperatures and a bright location. However, you should not be grown in full sun, as it threatens a heat accumulation. The plants should be watered in the growth phase often. In the resting phase, the watering should be reduced, without allowing an evaporation plant. In a culture in a pot, the substrate should be quite fine to feed the tender roots can.
The large species of the subgenus Brachycentron and the Section Holcoglossum can be cultivated tied up, but are best suited for a culture in baskets or pots. An exception is Holcoglossum subulifolium, which should be prevented in any case because of its overhanging growth. Is a regular watering guaranteed, so these species are best grown in a basket without substrate. Any and substrate that is used should be very coarse in structure to allow good air circulation to the roots. The plants need a very bright but cool location. They should be watered regularly, with drier periods during the rest phase. In the Jardin Botanique National de Belgique, Meise (Belgium) Holcoglossum be kimballianum in an alpine greenhouse held in the condensed own breathing and a parka must be worn. In nature, plants are exposed to during the heyday regularly rime they survive without any problems.
A successful culture often fails due to a permanently too warm culture or the use of too fine a substrate in which the roots die off due to lack of air.
Species
The following types list, divided into subgenera and sections, is based on the infrageneric system erected by Jin.
- Subgenus Brachycentron X.H. Jin & S. C. Chen Holcoglossum amesianum ( Rchb.f. ) Christenson
- Holcoglossum auriculatum ZJLiu, SCChen & XHJin
- Holcoglossum subulifolium ( Rchb.f. ) Christenson
- Section Holcoglossum Christenson Holcoglossum kimballianum ( Rchb.f. ) Garay
- Holcoglossum lingulatum ( Aver. ) Aver.
- Holcoglossum omeiense X.H.Jin & S.C.Chen
- Holcoglossum quasipinifolium ( Hayata ) Schltr.
- Holcoglossum wangii Christenson
- Holcoglossum flavescens ( Schltr. ) Z.H.Tsi
- Holcoglossum nujiangense X.H. Jin & S. C. Chen
- Holcoglossum rupestre ( Hand. - Mazz. ) Garay
- Holcoglossum sinicum Christenson
- Holcoglossum tsii T.Yukawa
- Holcoglossum weixiense X.H.Jin & S.C.Chen
The type Holcoglogssum calcicola Schuit & P.Bonnet recently described can be according to the authors, is not unique after by Jin (2005) integrated systems to classify. The type shows both features of the subgenus Holcoglossum and the subgenus Brachycentron.
Inter Generic hybrids
The following intergeneric hybrids with Holcoglossum be listed in the Royal Horticultural Society
- XHolcocentrum ( Holcoglossum x Ascocentrum )
- XHolcenda ( Holcoglossum x Ascocentrum x Vanda )
- XHolcosia ( Holcoglossum x Luisia )
- XHolcanthera ( Holcoglossum x Renanthera )
- XHolcodirea ( Holcoglossum x Sedirea )
- XHolcopsis ( Holcoglossum x Vandopsis )
- XMendelara ( Holcoglossum Ascocentrum x x x Neofinetia Rhynchostylis x Vanda )
- XVandoglossum ( Holcoglossum x Vanda )