Acostaea

Acostaea trilobata

The genus Acostaea the orchid family (Orchidaceae) comprises six species, all in South and Central America happen. The only inches small epiphytic plants grow and form dense clumps. The genus was named after Guillermo Acosta, a collector of orchids from Costa Rica.

Description

All species of this genus form of a creeping rhizome tightly packed upright, slender, enveloped by differ -ended low- leaves shoots. Each drive carries a leaf, this is oblong - oval to roundish shaped, wedge-shaped tapering and longer than the engine at the base into a short stalk. Leaf and shoot together measure only two to three centimeters.

The racemose inflorescence appears laterally from the base of the shoots and dominates the sheet slightly. The three to ten resupinierten flowers open in succession. The bracts include the pedicel tubular. The sepals are yellow, red or purple colored, the two sides are to grow together over the middle, the middle is the helmet-shaped bent over the column and at the bottom of some fused with the two lateral. The lateral petals are small, about as long as the column and triangular in shape. They are fused at their base with the base of the column, as well as the lip. This is unlobed, at its base originates a meaty, high vaulted and hairy callus. The column is winged upright and wide. The stamen is located at the end of the column and is bent down towards the column axis. The two yellow, pear-shaped pollinia are connected with short, broad stalks and Viscidien.

The plants of the subtribe Pleurothallidinae are usually pollinated by flies. In Acostaea the lip with the column foot is hinged. If the lip touches, it flips up and pushes it a sedentary insect against the column where it gets attached by means of sticky Viscidiums the pollinia, or possibly on the body of the insect existing pollinia on the stigma be placed.

Dissemination

The species of the genus Acostaea come from Costa Rica before to after Ecuador. They grow there as epiphytes in very wet forests at altitudes of 500 to 1,500 meters.

System

The genus Acostaea was mainly accrued on the basis of the movable lip. Sister taxon, according to a DNA study Pleurothallis costaricensis. However, the relationship to the genus Acostaea is composed of species that were previously different subgenera of Pleurothallis have been assigned. It is expected that further research will lead to taxonomic changes.

Six species have been described in this genus, other authors include only four and assign other taxa as a subspecies.

• Acostaea bicornis Luer (1983 ) Panama.
• Acostaea campylotyle P. Ortiz (1979), Colombia and northern Ecuador.
• Acostaea costaricensis Schltr. (1923 ) Costa Rica to Ecuador.
• Acostaea tenax Luer & R. Escobar (1982 ) Colombia.
• Acostaea trilobata Luer (1975 ) Ecuador.
• Acostaea unicornis Luer (1983 ) Panama.