''Nahuatlea aborescens'' is a species of tree in the

Composite Composite or compositing may refer to: Materials * Composite material, a material that is made from several different substances ** Metal matrix composite, composed of metal and other parts ** Cermet, a composite of ceramic and metallic material ...

family

endemic Endemism is the state of a species being found only 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 foun ...

to the Cape region and

Cerralvo Island Isla Cerralvo (), as is commonly named, whose official name is Isla Jacques Cousteau (; ), is an island located off the Cerralvo Canal coast near La Paz, Baja California Sur, Mexico. It is long with a land area of , and is the ninth-largest isl ...

Baja California Sur Baja California Sur, officially the Free and Sovereign State of Baja California Sur, is a state in Mexico. It is the 31st and last state to be admitted, in 1974. It is also the second least populated Mexican state and the ninth-largest state by ...

, commonly known as ocote. It grows up to 8 meters tall, with monoecious tan-colored flowers and short, leafy branchlets. It was formerly in the genus ''

Gochnatia ''Gochnatia'' is a genus of flowering plants in the daisy family, Asteraceae. It is named for botanist Frédéric Karl Gochnat. The genus contains mainly shrubs and subshrubs, with a few trees and herbs. All of the species are native to the Ame ...

'', where it was known commonly as the tree gochnatia.

Description

This plant grows in a

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...

habit, 3 to 8 m tall, and with a trunk 20 to 30 cm in diameter. The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are chartaceous (meaning resembling paper or parchment), and shaped ovate to elliptic,

glabrescent Glabrousness () is the technical term for a lack of hair, down, setae, trichomes, or other such covering. A glabrous surface may be a natural characteristic of all or part of a plant or animal, or be due to loss because of a physical condition, ...

(nearly smooth) on both faces. The leaf blades are 3.5 to 6.5 cm long by 2.5 to 4.5 cm wide. The leaf

petiole Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...

is 5 mm long. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is crowded at the ends of the branches. The

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 ...

are solitary or more usually in loose clusters of 2 to 20 at the apex of the branches, with few clusters per plant. There are 13 to 20

flowers Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

per head, with yellowish corollas, 12 mm long. The

involucre In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also look ...

is shaped cylindrical to narrowly obconic depending on age, and is 10 to 15 mm tall by 6 to 8 mm wide at

anthesis Anthesis is the period during which a flower is fully open and functional. It may also refer to the onset of that period. The onset of anthesis is spectacular in some species. In ''Banksia'' species, for example, anthesis involves the extension ...

, with the bracts in 8 to 10 series.

Taxonomy

This species was first described by

Townshend Stith Brandegee Townshend Stith Brandegee (February 16, 1843 – April 7, 1925) was an American botanist. He was an authority on the flora of Baja California and the Channel Islands of California, Channel Islands of California. Early life Brandegee was born on ...

as ''Gochnatia arborescens'' in 1903. In later years, it was discovered that the genus ''

'' was not

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

, but in fact composed of a number of distinct

clades In biology, a clade (), also known as a monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy ...

. The Mexican species of ''Gochnatia'' were then combined into a new genus ''

Nahuatlea ''Nahuatlea'' is a genus of flowering plants in the sunflower family, Asteraceae. It includes seven species which range from southern Texas to southern Mexico. The species which constitute genus ''Nahuatlea'' were originally placed in genus ''Go ...

'', by

Vicki Funk Vicki Ann Funk (November 26, 1947 – October 22, 2019) was an American botanist and curator at the Smithsonian's National Museum of Natural History, known for her work on members of the composite family (Asteraceae) including collecting plants ...

in 2017. Funk suggested that the genus originated from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

in a dispersal event, evidenced by the fact that the Mexican ''Gochnatia'' (now ''Nahuatlea'') are more morphologically similar to the

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

members of ''Gochnatia''.

Distribution and habitat

This species is

to the state 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 ...

, which is on the Baja California Peninsula. It is distributed from the Sierra de La Giganta to the Cape region of the peninsula and on

in the

Gulf of California The Gulf of California (), also known as the Sea of Cortés (''Mar de Cortés'') or Sea of Cortez, or less commonly as the Vermilion Sea (''Mar Vermejo''), is a marginal sea of the Pacific Ocean that separates the Baja California peninsula from ...

. It is found in arroyos and along roads in agricultural areas.

References

{{Taxonbar, from=Q90496608 Gochnatioideae Trees of Northern America Endemic flora of Mexico Natural history of the Peninsular Ranges Flora of Baja California Sur Plants described in 1903 Taxa named by Townshend Stith Brandegee