Cypripedioideae

Yellow Lady's Slipper ( Cypripedium calceolus )

The Cypripedioideae are a subfamily of the orchid family ( Orchidaceae). With about 120 species in five genera, it represents one of the smaller of the five subfamilies of this plant family

Features

All representatives of Cypripedioideae are perennial, herbaceous plants. The fleshy roots sometimes have velamen. The leaves are spirally arranged or distichous, the shoot is slender or compressed. In the bud, the leaves are rolled and the leaf blade is Plikat (folded) or the leaves are folded in the bud, smooth and leathery. There is no separating tissue between leaf and shoot.

The inflorescences are terminal and the Cypripedioideae usually unbranched. The flowers are spirally or two lines on the shoot, they are 'upside. The petals are available in two threefold circles, with usually two petals of the outer circle are fully grown. The labellum forms a sac-like structure. The ovary is inferior and single chamber or dreikammerig. Two fertile stamens, a Staminodium and the pen have grown into a complex structure. The style is short and thick, the scar large and convex, the median stigma lobes larger than the two lateral ones. The two lateral stamens are fertile, the pollen grains are glued together to form a paste or shaped in some Phragmipedium species related pollinia. The mean, barren stamen is broadened peltate. The fruits are mostly fruit capsules in Selenipedium beer similar. They contain numerous flattened seeds, about one millimeter long and 0.1 mm wide. The seeds of Selenipedium notwithstanding, are lens-shaped and provided with a hard seed coat.

The chromosome numbers vary within the subfamily over a wide range of 2n = 20 in Cypripedium up to 26 to 44 chromosomes in Paphiopedilum. The chromosomes are quite large.

The species of this subfamily make you fall flowers, in which the access for insects in the sac-like lip of the front is pretty easy. The interior is designed so that the insects to the stigma and the stamens by climbing out of the flower and thereby pollinate the flower.

Dissemination

The types of Cypripedioideae can be found in northern South America and Central America ( Mexipedium, Phragmipedium, Selenipedium ) zirkumboreal in North America, Europe and northern Asia ( Cypripedium ), and in the subtropical and tropical South East Asia ( Paphiopedilum ). In Australia and Africa, they do not occur. The spread could have come from a center of origin in Central America.

System

The togetherness of the five genera is undisputed for a long time. Their differing number of fertile stamens (two versus one other orchids) led to the suggestion to consider them as a separate family Cypripediaceae. Molecular genetic studies support the inclusion in the Orchidaceae and confirm the relationship of the five genera. A position as a sister taxon to all other orchids with the exception of Apostasioideae is discussed.

  • Selenipedium
  • Cypripedium
  • Mexipedium, with the only kind Mexipedium xerophyticum
  • Phragmipedium
  • Paphiopedilum

Documents

  • A.V. Cox, A. M. Pridgeon, V.A. Albert, M. W. Chase ( 1997): Phylogenetics of the slipper orchids ( Cypripedioideae, Orchidaceae): nuclear rDNA ITS sequences. Pl Syst. Evol. 208:197-223. Online, accessed on 17 October 2007
  • Robert L. Dressler (1993 ): Phylogeny and Classification of the Orchid Family. Pp. 85ff. Cambridge University Press, ISBN 0-521-45058-6
  • KM Cameron et al (1999): A phylogenetic analysis of the Orchidaceae: evidence from rbcL nucleotide sequences. American Journal of Botany 86:208-224. Online, accessed on 17 October 2007
John Lindley Genus Resupination Labellum (botany) Ovary (botany) Stigma (botany) Pollinium Berry
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