Epidendrum lacustre is a sympodial orchid

Orchidaceae

The Orchidaceae, commonly referred to as the orchid family, is a morphologically diverse and widespread family of monocots in the order Asparagales. Along with the Asteraceae, it is one of the two largest families of flowering plants, with between 21,950 and 26,049 currently accepted species,...

 which is known to grow both epiphytically

Epiphyte

An epiphyte is a plant that grows upon another plant non-parasitically or sometimes upon some other object , derives its moisture and nutrients from the air and rain and sometimes from debris accumulating around it, and is found in the temperate zone and in the...

 and lithophytically

Lithophyte

Lithophytes are a type of plant that grows in or on rocks. Lithophytes feed off moss, nutrients in rain water, litter, and even their own dead tissue....

 in the cloud forest

Cloud forest

A cloud forest, also called a fog forest, is a generally tropical or subtropical evergreen montane moist forest characterized by a persistent, frequent or seasonal low-level cloud cover, usually at the canopy level. Cloud forests often exhibit an abundance of mosses covering the ground and...

s and rainforest

Rainforest

Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...

s of Colombia

Colombia

Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...

, Costa Rica

Costa Rica

Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....

, Ecuador

Ecuador

Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...

, Nicaragua

Nicaragua

Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...

, Peru

Peru

Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

 and Venezuela

Venezuela

Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...

 at altitudes ranging from 1.2—2.5 km. The type of this species was found growing "on half-submerged rotten trees" in a Venezuelan marsh at an altitude of 2.4 km.

Description

E. lacustre was placed in the subgenus E. subg. Spathium

Epidendrum subg. Spathium

John Lindley published Epidendrum subg. Spathium of the Orchidaceae. According to Lindley's diagnosis,, the E. subg. Spathium is recognizable by is sympodial habit with individual stems being slender and covered by the bases of the distichous leaves, by the lip of the flower being...

 by Reichenbach; as is typical of plants in this subgenus, E. lacustre stems are unswollen and covered by sheathes which bear distichous leaves on the upper part of the stem, and end in one or more apical spathes, through which the inflorescence erupts. E. lacustre stems grow to 1.2 m tall. The leaves are broad and obtuse, to 21 cm long by 7 cm wide. The .3—.4 m long peduncle

Peduncle (botany)

In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...

 grows from a double, scimitar-shaped spathe, and bears the large (to 8 cm across) flowers near the end in an almost umbellate raceme

Raceme

A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...

. The 12 cm pedicel is four times the length of the ovary. The widely open green sepals and petals are linear with pointed tips. The white lip

Labellum

Labellum is the Latin diminutive of labium, meaning lip. These are anatomical terms used descriptively in biology, for example in Entomology and botany.-Botany:...

 is adnate

Adnation

Adnation in plants is the "union of unlike parts; organically united or fused with another dissimilar part, e.g. an ovary to a calyx tube, or stamens to petals". This is in contrast to connation, the fusion of similar organs....

 to the column

Column (botany)

The column, or technically the gynostemium, is a reproductive structure that can be found in several plant families: Aristolochiaceae, Orchidaceae, and Stylidiaceae....

to its apex, nearly cordate where it diverges from the column, either barely divided into three lobes or undivided, and pointed at the distal end. The callus consists of two pointed lumps just beyond the column, separated by a 4 cm long raised keel.