Pseudocentrum
Pseudo Centrum is a genus of the orchid family ( Orchidaceae). It consists of seven species of herbaceous plants that are native to tropical America.
Description
The species of the genus Pseudomonas Centrum are terrestrial growing herbaceous plants with ascending, rhizomartiger base and fleshy roots. Multiple sheets of paper are in a loose rosette. They are stalked, the leaf blade is lanceolate to oval.
The racemose, terminal inflorescence is more or less densely covered with numerous flowers. The inflorescence stalk bears several bracts. The ovary is stalked depending on the type or sessile, glabrous or hairy. The flowers appear 'upside. The dorsal sepal is free, rather narrow, more less hood -shaped, sometimes repulsed. The lateral sepals are fused together in different ways, either they form a long, spur -like tube or a helmet, their tips are free, meaty and spread. The petals are narrow and adhere to the side of the column, about from the center they are free and repulsed. The lip is united at the base with the column, three-lobed, the lateral lobes are parallel to the column, the middle lobe is long and linear, the edges bent rinnig, completely hidden from the coalesced part of the sepals. The column is very short, laterally with two wings of the base to the scar. The scar is transverse to the column axis oval, the edges are thickened. The stamen contains two chambers of unequal size four pollinia. These depend on stalks at a small viscid disc ( Viscidium ). The separation between scar tissue and stamen ( rostellum ) is straight, it ends pointed undressed.
Occurrence
Pseudo Centrum occurs in the Andes of South America from Peru to Ecuador Colombia and on to Panama and Costa Rica, also on some islands of the Caribbean. There are colonized 1700-3200 meters altitude. The sites are shaded moist woods.
Systematics and botanical history
The genus Pseudomonas Centre was set up in 1858 by Lindley. The name comes from the Greek words pseudos ψεῦδος, "wrong", and κέντρον kentron, " spur " together. It refers to the fact that the spur is not formed by the lip, but the outer petals. Type species Pseudomonas Centrum is macrostachyum.
Pseudo Centrum is classified within the tribe Cranichideae in the subtribe Cranichidinae.
The following species are known:
- Pseudo Centrum bursarium Rchb.f.
- Pseudo Centrum guadalupense Cogn. in I.Urban
- Pseudo Centrum hoffmannii ( Rchb.f. ) Rchb.f.
- Pseudo Centrum macrostachyum Lindl.
- Pseudo Centrum minus Benth.
- Pseudo Centrum purdii Garay
- Pseudo Centrum sylvicolum Rchb.f.