Xerorchis is a orchid genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 in the subfamily Epidendroideae

Epidendroideae

In plant systematics Epidendroideae is a subfamily of the orchid family, Orchidaceae. Epidendroideae is larger than all the other orchid subfamilies together, comprising more than 15,000 species in 576 genera. Most Epidendroid orchids are tropical epiphytes, typically with pseudobulbs...

, and the sole representative of tribe Xerorchideae. This is a very primitive genus consisting of terrestrial orchids. Xerorchis thrives in South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

.

Taxonomy

It is unclear whether this genus should be classified in the lower or higher epidendroids.

Xerorchis has 8 pollinia

Pollinium

Pollinium, or plural pollinia, is a coherent mass of pollen grains in a plant.They are the product of only one anther, but are transferred, during pollination, as a single unit. This is regularly seen in plants such as orchids and many species of milkweeds .Most orchids have waxy pollinia...

, hence similar to the more advanced epidendroid genera of Epidendreae

Epidendreae

The tribe Epidendreae of the Orchidaceae comprises six subtribes:* Bletiinae sensu MMIV, which contains only the genera Basiphyllaea, Bletia, and Hexalectris* Chysinae* Coeliinae* Laeliinae* Pleurothallidinae* Ponerinae...

 and Arethuseae

Arethuseae

Arethuseae is a mid-sized tribe of orchids in the subfamily Epidendroideae. This tribe was initially categorized by John Lindley in 1840. Its largest subtribes at Arethusinae and Bletiinae, in addition to the smaller subtribes Sobraliinae and Thuniinae....

. Yet its morphology

Morphology (biology)

In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....

, with unthickened stems

Plant stem

A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...

 and persistent leaves

Leaf

A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

, is that of a bambusoid grass

Grass

Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...

 and makes it more similar to Tropidieae or Triphoreae.