''Chloracantha'' 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 () is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger fam ...

, containing the single species ''Chloracantha spinosa''. It is distributed in the southwestern and south-central United States ( CA NV AZ UT NM TX OK LA), most of

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

, and much of

Central America Central America is a subregion of North America. Its political boundaries are defined as bordering Mexico to the north, Colombia to the southeast, the Caribbean to the east, and the Pacific Ocean to the southwest. Central America is usually ...

. Its

English language English is a West Germanic language that developed in early medieval England and has since become a English as a lingua franca, global lingua franca. The namesake of the language is the Angles (tribe), Angles, one of the Germanic peoples th ...

common names include spiny chloracantha, spiny aster, devilweed aster, and Mexican devilweed.''Chloracantha spinosa''.
Integrated Taxonomic Information System (ITIS). In

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many countries in the Americas **Spanish cuisine **Spanish history **Spanish culture ...

it is known as ''espina de agua'', ''espinaza'', and ''espinosilla''. This species is a perennial herb or

subshrub A subshrub (Latin ''suffrutex'') or undershrub is either a small shrub (e.g. prostrate shrubs) or a perennial that is largely herbaceous but slightly woody at the base (e.g. garden pink and florist's chrysanthemum). The term is often interch ...

; its green stems look more herbaceous than woody, "but it behaves more like a subshrub",''Chloracantha''.
Flora of North America. with its tough stems living for several years and rapidly developing vascular cambia. The stems are hairless and sometimes waxy in texture, and some of the lateral branches may be sharply angled and reduced in size, becoming thorns. The alternately arranged leaves persist for only a short time and then fall away. Large colonies of these bare stems proliferate from a robust

rhizome In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from ...

s. The stems usually reach a maximum height around 1.5 meters, but can well exceed 2 meters at times. They bear loose arrays of many

flower heads A pseudanthium (; : pseudanthia) 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, composite flowers ...

each roughly half a centimeter long and wide. The head is lined with layers of hairless

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 o ...

. It contains up to 33 coiling white

ray florets Asteraceae () is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger fa ...

and many yellow

disc floret Asteraceae () is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger fa ...

s. The fruit is a cypsela with a pappus of many barbed bristles. This plant is known from dry habitat and moist spots, such as streambanks and

seeps A petroleum seep is a place where natural liquid or gaseous hydrocarbons escape to the Earth's atmosphere and surface, normally under low pressure or flow. Seeps generally occur above either natural terrestrial or underwater petroleum accumul ...

. It tolerates some saline habitat types.''Chloracantha spinosa'' var. ''spinosa''.
The Jepson eFlora 2013. ;varieties # ''Chloracantha spinosa'' var. ''spinosa'' # ''Chloracantha spinosa'' var. ''jaliscensis'' (McVaugh) S.D. Sundb. -

Jalisco Jalisco, officially the Free and Sovereign State of Jalisco, is one of the 31 states which, along with Mexico City, comprise the 32 Political divisions of Mexico, Federal Entities of Mexico. It is located in western Mexico and is bordered by s ...

Nayarit Nayarit, officially the Free and Sovereign State of Nayarit, is one of the 31 states that, along with Mexico City, comprise the Political divisions of Mexico, Federal Entities of Mexico. It is divided in Municipalities of Nayarit, 20 municipalit ...

# ''Chloracantha spinosa'' var. ''spinosissima'' (Brandegee) S.D.Sundb. -

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

# ''Chloracantha spinosa'' var. ''strictospinosa'' S.D.Sundb. -

Chiapas Chiapas, officially the Free and Sovereign State of Chiapas, is one of the states that make up the Political divisions of Mexico, 32 federal entities of Mexico. It comprises Municipalities of Chiapas, 124 municipalities and its capital and large ...

Michoacán Michoacán, formally Michoacán de Ocampo, officially the Free and Sovereign State of Michoacán de Ocampo, is one of the 31 states which, together with Mexico City, compose the Political divisions of Mexico, Federal Entities of Mexico. The stat ...

Costa Rica Costa Rica, officially the Republic of Costa Rica, is a country in Central America. It borders Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, and the Pacific Ocean to the southwest, as well as Maritime bo ...

El Salvador El Salvador, officially the Republic of El Salvador, is a country in Central America. It is bordered on the northeast by Honduras, on the northwest by Guatemala, and on the south by the Pacific Ocean. El Salvador's capital and largest city is S ...

Guatemala Guatemala, officially the Republic of Guatemala, is a country in Central America. It is bordered to the north and west by Mexico, to the northeast by Belize, to the east by Honduras, and to the southeast by El Salvador. It is hydrologically b ...

Honduras Honduras, officially the Republic of Honduras, is a country in Central America. It is bordered to the west by Guatemala, to the southwest by El Salvador, to the southeast by Nicaragua, to the south by the Pacific Ocean at the Gulf of Fonseca, ...

Nicaragua Nicaragua, officially the Republic of Nicaragua, is the geographically largest Sovereign state, country in Central America, comprising . With a population of 7,142,529 as of 2024, it is the third-most populous country in Central America aft ...

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

References

External links

''Chloracantha spinosa''.
USDA PLANTS.
''Chloracantha spinosa''.
CalPhotos. Monotypic Asteraceae genera Flora of Mexico Flora of the United States Flora of Central America Astereae {{Astereae-stub