Sobralia

Sobralia dichotoma

The genus Sobralia from the orchid family (Orchidaceae) is widespread with about 100 species in Central and South America.

Description

Sobralia includes perennial plants that grow terrestrially rare, lithophytic or epiphytic. They are often quite large and robust, depending on the type of unbranched shoot growth heights of a few centimeters can reach up to ten meters. The roots are fleshy and surrounded by a two to five cell layers thick velamen radicum. The two lines arranged leaves are sessile, the leaf base includes the stems. The leaf blade is usually leathery fixed, rarely thin, but always crinkled along the Vein to a certain degree ( Plikat ).

The inflorescence is terminal or lateral, with or without peduncle, simple or branched. The resupinierten flowers usually sit crowded together so that the bracts overlapping cone-like. The large, colorful flowers open in succession and usually fade after one day. The plants of a population bloom usually exactly the same time. The petals are not fused together and, except for the lip, each about the same. The petals are sometimes broader than the three outer petals. The lip is typically more visible than the other petals. It is entire or three-lobed, with the base of the column comprehensive, continued to spread in front, filled with various bars or toothed combs. The column is slender club-shaped, laterally winged thin, the wing ending in a pair of curved appendages on either side of the scar. The scar is bean-shaped, transverse to the column axis, usually slightly protruding. The separation between scar tissue and stamen ( rostellum ) is large and convex. The two -chambered stamen stands at the end of the column and is bent down towards the column axis. The pollinia can than eight pieces, two of which are related, are interpreted, or as four pieces that are bent in a U - shaped and divided into two parts. The consistency of the pollinia is mealy.

As pollinators (Bombus ) were observed in Sobralia orchid bees ( Euglossini ) and bumblebees. Sobralia amabilis is pollinated by hummingbirds.

Dissemination

Sobralia grows in tropical America, from Mexico to the north over the whole of Central America and the northern half of South America. Sobralia comes at altitude prior to 3300 meters.

System

The genus Sobralia together with Elleanthus and Sertifera the tribe Sobralieae. Within the subfamily Epidendroideae, this tribe a basal line dar. Sobralia is the sister taxon to a clade from the other two genera.

Ruiz and Pavón described the genus in 1794. Lectotype is Sobralia dichotoma. The genus name honors the Sobralia Spanish physician and botanist Francisco Sobral.

The species of the genus Sobralia was already divided by Lindley in 1854 in three groups. Only Brieger 1983 revised this classification, named the groups and each laid down type species. A recent revision was made by Robert L. Dressler, then there are five sections and some species can be classified only with difficulty.

• Sect. Abbreviatae - The inflorescence axis is compressed and densely covered with bracts, the flowers bloom in succession on. With about 50 species the largest section, type species Sobralia fimbriata.
• Sect. Globosae - The compressed inflorescence axis continues to grow and produces flowers over several growing seasons. About four species to Sobralia candida.
• Sect. Intermediae - The inflorescence axis is strongly compressed and densely covered with bracts, each one or two flowers blooming. About 15 species to Sobralia fragrans.
• Sect. Racemosae - With long inflorescence axis and long bracts. About eight species to Sobralia rosea.
• Sect. Sobralia - the section that contains the type species ( Sobralia dichotoma). After Brieger characterized by axillary inflorescences, but better characterized, according to Dressler by short bracts and long inflorescence axis. Contains about 13 species.