''Chiliophyllum'' is a

monotypic genus In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

of flowering plants in the aster family,

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae ...

, containing the single species ''Chiliophyllum densifolium''. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, t ...

, where it is known only from

Mendoza Province Mendoza, officially Province of Mendoza, is a province of Argentina, in the western central part of the country in the Cuyo region. It borders San Juan to the north, La Pampa and Neuquén to the south, San Luis to the east, and the republic ...

.Bonifacino, J. M. (2009)
Taxonomic revision of the ''Chiliotrichum'' Group sensu stricto (Compositae: Astereae).
''Smithsonian Contributions to Botany'' 92. pg. 21. Its local common names include ''romero del piche'' and ''romero pichi''. This species is a member of the ''Chiliotrichum'' Group in the tribe

Astereae Astereae is a tribe of plants in the family Asteraceae that includes annuals, biennials, perennials, subshrubs, shrubs, and trees. They are found primarily in temperate regions of the world. Plants within the tribe are present nearly worldwide d ...

of the aster family. This group includes many related "shrubby daisies" native to South America. ''Chiliophyllum densifolium'' is the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

of its genus, described from Mendoza Province in 1862. Two more species were added to the genus, but in 2009 ''C. fuegianum'' was transferred to ''Chiliotrichum'' and ''C. andinum'' was moved to a genus of its own, '' Cabreraea'', leaving ''C. densifolium'' the sole member of ''Chiliophyllum''. This plant is a spreading, somewhat rounded shrub growing up to 1.7 meters tall. Its herbage is gland-dotted and sometimes has woolly hairs. The branches are covered densely in leaves; the genus name ''Chiliophyllum'' is from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

' ("thousand") and ' ("leaf"), a reference to the abundant leaves, and the species name ''densifolium'' also refers to the dense foliage. The leathery, glandular leaf blades are 5 to 6 millimeters long and teardrop-shaped.

Flower heads A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, compos ...

occur singly at the tips of the branches. They are cylindrical with layers of glandular

phyllaries In botanical terminology, a phyllary, also known an involucral bract or tegule, is a single bract of the involucre of a composite flower. The involucre is the grouping of bracts together. Phyllaries are reduced leaf-like structures that form one ...

that have membranous edges. The heads contain 4 to 8 yellow ray florets tipped with three lobes and up to 12 tubular yellow disc florets tipped with five curled lobes. The fruit is a ribbed

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not op ...

up to a centimeter long including its pappus of many narrow scales. This species only occurs in the

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

of central Argentina, where it grows in rocky mountainous habitat at elevations between 2000 and 2600 meters. Associated flora includes ''

Nassauvia axillaris ''Nassauvia'' is a genus of flowering plants in the tribe Nassauvieae within the family Asteraceae. It is native to Argentina, Bolivia, Chile and the Falkland Islands. ''Nassauvia'' is said to be chocolate scented. Species Formerly included ...

'', ''

Berberis buxifolia ''Berberis microphylla'', common name box-leaved barberry and Magellan barberry, in Spanish calafate and michay and other names, is an evergreen shrub, with simple, shiny box-like leaves. The calafate is native to southern Argentina and Chile a ...

'', and species of ''

Ephedra Ephedra may refer to: * Ephedra (medicine), a medicinal preparation from the plant ''Ephedra sinica'' * ''Ephedra'' (plant), genus of gymnosperm shrubs See also * Ephedrine Ephedrine is a central nervous system (CNS) stimulant that is oft ...

'' and '' Adesmia''. The plant is used medicinally as a

diuretic A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics in ...

mixed with

yerba mate Yerba mate or yerba-maté (''Ilex paraguariensis''; from Spanish ; pt, erva-mate, or ; gn, ka'a, ) is a plant species of the holly genus ''Ilex'' native to South America. It was named by the French botanist Augustin Saint-Hilaire. The leav ...

mate Mate may refer to: Science * Mate, one of a pair of animals involved in: ** Mate choice, intersexual selection ** Mating * Multi-antimicrobial extrusion protein, or MATE, an efflux transporter family of proteins Person or title * Friendship * ...

References

{{Taxonbar, from1=Q5098968, from2=Q15592946 Astereae Monotypic Asteraceae genera Endemic flora of Argentina