Madrean Region
Encyclopedia
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, as delineated by Armen Takhtajan
Armen Takhtajan
Armen Leonovich Takhtajan or Takhtajian , was a Soviet-Armenian botanist, one of the most important figures in 20th century plant evolution and systematics and biogeography. His other interests included morphology of flowering plants, paleobotany, and the flora of the Caucasus...
and Robert F. Thorne. It occupies arid or semiarid areas in the southwestern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and northwestern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
and is bordered by the Rocky Mountain Region
Rocky Mountain Region
The Rocky Mountain Floristic Region, also known as the Rocky Mountain Floristic Province, is a floristic region within the Holarctic Kingdom in western North America delineated by Armen Takhtajan and Robert F...
and North American Atlantic Region
North American Atlantic Region
North American Atlantic Region is a floristic region within the Holarctic Kingdom identified by Armen Takhtajan and Robert F. Thorne, spanning from the Atlantic and Gulf coasts to the Great Plains and comprising a major part of the United States and southeastern portions of Canada...
of the Holarctic Kingdom in the north and in the east, as well as by the Caribbean Region of the Neotropical Kingdom in the south.
The Madrean Region is characterized a very distinct flora
Flora
Flora is the plant life occurring in a particular region or time, generally the naturally occurring or indigenous—native plant life. The corresponding term for animals is fauna.-Etymology:...
with at least three endemic families
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
(Fouquieriaceae, Simmondsiaceae
Simmondsiaceae
Simmondsiaceae or the Jojoba Family is a family of flowering plants. The family is not recognized by all taxonomic systems, the single species, Simmondsia chinensis, often being treated as belonging to family Buxaceae....
, and Setchellanthaceae). Crossosomataceae
Crossosomataceae
Crossosomataceae is a small plant family, consisting of three genera of shrubs found only in the dry parts of the American southwest and Mexico.-External links:...
, Garryaceae
Garryaceae
Garryaceae is a small family of dicotyledons, including only two genera:*Garrya Douglas ex Lindl., 1834. About 16-18 species.*Aucuba Thunb., 1783. About 3-10 species....
, Lennoaceae
Lennoaceae
Lennooideae is a subfamily of parasitic flowering plants of south-western North America and north-western South America.The relationships of this subfamily with other plants remains uncertain. Traditionally it was treated at family rank as Lennoaceae, and placed in different orders by different...
, Limnanthaceae
Limnanthaceae
Limnanthaceae are a small family of annual herbs occurring throughout temperate North America. There are eight species and nineteen taxa currently recognized. Members of this family are prominent in vernal pool communities of California. Some taxa have been domesticated for use as an oil seed crop...
and Stegnospermataceae
Stegnospermataceae
Stegnospermataceae is a family of flowering plants.The family has only been recognized by a few taxonomists, the plants in it more commonly assigned to the family Phytolaccaceae...
have their principal development here; for Onagraceae
Onagraceae
Onagraceae, also known as the Willowherb family or Evening Primrose family, are a family of flowering plants. The family includes about 640-650 species of herbs, shrubs, and trees in 20-24 genera...
, Polemoniaceae
Polemoniaceae
Polemoniaceae are a family of about 25 genera with 270-400 species of annual and perennial plants, native to the Northern Hemisphere and South America, with the center of diversity in western North America, especially in California.Only one genus is found in Europe, and two in Asia, where they...
and Hydrophyllaceae
Hydrophyllaceae
Hydrophylloideae is a subfamily of the Boraginaceae family of flowering plants. Their taxonomic position is somewhat uncertain. Traditionally, and under the Cronquist system, they were given family rank under the name Hydrophyllaceae, and treated as part of the order Solanales...
it is the major center of diversity. More than 250 genera
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...
and probably more than half of the species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of the region are endemic to it according to Takhtajan.
Floristic provinces
The region is subdivided into four floristic provinces:- Great Basin ProvinceGreat BasinThe Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...
- Californian ProvinceCalifornia Floristic ProvinceThe California Floristic Province is a floristic province with a Mediterranean climate located on the Pacific Coast of North America with a distinctive flora that bears similarities to floras found in other regions experiencing a winter rainfall, summer drought climate like the Mediterranean...
- Sonoran ProvinceSonoran DesertThe Sonoran Desert is a North American desert which straddles part of the United States-Mexico border and covers large parts of the U.S. states of Arizona and California and the northwest Mexican states of Sonora, Baja California, and Baja California Sur. It is one of the largest and hottest...
- Mexican Highlands ProvinceMexican PlateauThe Central Mexican Plateau, also known as the Mexican Altiplano or Altiplanicie Mexicana, is a large arid-to-semiarid plateau that occupies much of northern and central Mexico...
Great Basin Province
The Great Basin Province includes most of the Great BasinGreat Basin
The Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...
. It shares much of its flora with the neighboring provinces and has but few endemic genera
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...
. Species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
endemism is also moderate (about 25%), but is much more considerable in such genera as Astragalus
Astragalus
Astragalus is a large genus of about 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae, subfamily Faboideae. The genus is native to temperate regions of the Northern Hemisphere...
, Eriogonum
Eriogonum
Eriogonum is the scientific name for a genus of flowering plants, in the family Polygonaceae. The genus is found in North America and is known as wild buckwheat. This is a highly species-rich genus, and indications are that active speciation is continuing...
, Penstemon
Penstemon
Penstemon , Beard-tongue, is a large genus of North American and East Asian plants traditionally placed in the Scrophulariaceae family. Due to new genetic research, it has now been placed in the vastly expanded family Plantaginaceae...
, Cymopterus
Cymopterus
Cymopterus is a genus of perennial plants in the Apiaceae. They are commonly known as the spring parsleys. They are short, squat plants with long taproots.Species include:* Cymopterus aboriginum* Cymopterus beckii...
, Lomatium
Lomatium
Lomatium is a genus of 70 to 80 perennial herbs native to western North America.Several species, including L. cous, L. geyeri, and L. macrocarpum, are sometimes known as biscuit roots for their starchy edible roots. These are or have been traditional Native American foods, eaten cooked or dried...
, Cryptantha
Cryptantha
Cryptantha is a genus of hairy plants in the borage family . Some of them are heterostylous.- Selected species :*Cryptantha abata: Abata Cryptantha, Dent-nut Catseye, Dentnut Cryptantha...
, Chrysothamnus
Chrysothamnus
Chrysothamnus is a member of the plant family Asteraceae. It is a semi-deciduous shrub, sometimes also called sagebrush. The native distribution is in the arid western United States and northern Mexico...
, Erigeron
Erigeron
Erigeron is a genus of about 390 species of flowering plants in the family Asteraceae. The genus has a cosmopolitan distribution with the highest species diversity in North America, where 173 species occur....
, Phacelia
Phacelia
Phacelia is a genus of about 200 species of annual or perennial herbaceous plants, native to North and South America....
, Castilleja
Castilleja
Castilleja, commonly known as Indian paintbrush or Prairie-fire, is a genus of about 200 species of annual and perennial herbaceous plants native to the west of the Americas from Alaska south to the Andes, northern Asia, and one species as far west as the Kola Peninsula in Siberia...
, and Gilia
Gilia
Gilia is a genus of between 25 and 50 species of flowering plants in the family Polemoniaceae, native to temperate and tropical regions of the Americas, from the western United States south to northern Chile, where they occur mainly in desert or semi-desert habitats.They are herbaceous annuals,...
. The vegetation is dominated by Artemisia species and Chenopodiaceae
Chenopodiaceae
Chenopodiaceae were a family of flowering plants, also called the Goosefoot Family. They are now included within family Amaranthaceae. The vast majority of Chenopods are weeds, and many are salt and drought tolerant. A few food crops also belong to the family: spinach, beets, chard, quinoa, and...
in the central part of the province.
Californian Province
The Californian Province occupies Central and Southern CaliforniaCalifornia
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
from the seashore to the foothills of the Cascade Range
Cascade Range
The Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades...
, the Sierra Nevada range, and northern parts of Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
in Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. It possesses the most diverse flora within the floristic region. About half of the species are endemic. More than 50 genera (e.g. Adenostoma
Adenostoma
Adenostoma is a genus of shrubs containing only two species: Adenostoma fasciculatum , and Adenostoma sparsifolium . Both are native to coastal California and Baja California, while A...
, Bergerocactus, Carpenteria
Carpenteria
Carpenteria californica , the sole species in the genus Carpenteria, is an evergreen shrub native to California. It is closely related to the genus Philadelphus...
, Cneoridium
Cneoridium
Cneoridium is a monotypic genus in the citrus family which contains the single species Cneoridium dumosum, known by the common name bushrue.-Description:...
, Dendromecon
Dendromecon
Dendromecon, the tree poppy, is a genus of one or two species of shrubs to small trees, native to California and northern Baja California. The leaves are evergreen, alternate, lanceolate to ovate, 3-10 cm long...
, Fremontodendron, Jepsonia
Jepsonia
Jepsonia is a small genus of flowering plants containing three species. The Jepsonia is a perennial with a cormlike caudex, toothed leaves, and a cyme inflorescence that blooms in the fall...
, Lyonothamnus
Lyonothamnus
Lyonothamnus is a monotypic genus of trees in the rose family containing the single species Lyonothamnus floribundus, which is known by the common name Catalina ironwood, and the subspecies ssp. aspleniifolius and ssp...
, Neostapfia
Neostapfia
Neostapfia is a monotypic genus containing the single species of grass Neostapfia colusana, which is known by the common name Colusa grass.-Distribution:It is endemic to the Central Valley of California, where it grows in vernal pools...
, Odontostomum
Odontostomum
Odontostomum is a monotypic genus genus of flowering plants containing the single species Odontostomum hartwegii, which is known by the common name Hartweg's doll's-lily. In the APG III classification system, it is placed in the family Tecophilaeaceae. It was formerly placed in the Liliaceae...
, Ornithostaphylos
Ornithostaphylos
Ornithostaphylos is a monotypic plant genus which contains the single species Ornithostaphylos oppositifolia, the Baja birdbush or Baja California birdbush. This is a shrub native to the chaparral plant community of the coastline of southern California and northern Baja California. This bush has...
, Pickeringia, Romneya) are endemic or near-endemic as well. Arctostaphylos
Arctostaphylos
Arctostaphylos is a genus of plants comprised by the manzanitas and bearberries. They are shrubs or small trees.There are about 60 species of Arctostaphylos, ranging from ground-hugging arctic, coastal, and mountain species to small trees up to 6 m tall. Most are evergreen , with small oval...
, Brodiaeinae, Calochortus
Calochortus
Calochortus is a genus of bulbous plants that includes 70 species from British Columbia to Guatemala and east to Nebraska. Calochortus is the most widely dispersed genus of Liliaceae on the North American Pacific coast. Of these, 28 species are endemic to California...
, Caulanthus
Caulanthus
Caulanthus is a genus of plants in the mustard family. Plants of this genus may be known as jewelflowers. They are also often referred to as wild cabbage, although this common name usually refers to wild variants of Brassica oleraceae, the cabbage plant...
, Streptanthus
Streptanthus
Streptanthus is a genus within the mustard family, Brassicaceae. There are about 35 known species within the Streptanthus genus, distributed mostly throughout western North America. The common names for this genus are Jewelflower and Twistflower...
, Ceanothus
Ceanothus
Ceanothus L. is a genus of about 50–60 species of shrubs or small trees in the buckthorn family Rhamnaceae. The genus is confined to North America, the center of its distribution in California, with some species in the eastern United States and southeast Canada, and others extending as far south...
, Cryptantha
Cryptantha
Cryptantha is a genus of hairy plants in the borage family . Some of them are heterostylous.- Selected species :*Cryptantha abata: Abata Cryptantha, Dent-nut Catseye, Dentnut Cryptantha...
, Downingia
Downingia
Downingia is a genus of 13 annual plants native to western North America and Chile. Commonly known as "calicoflowers", they are notable for forming mass displays of small but colorful blooms around vernal pools...
, Dudleya
Dudleya
Dudleya is a genus of succulent perennials, consisting of about 45 species in southwest North America.Many plants in the Dudleya genus were formerly classified as Echeveria....
, Eritrichieae, Eriogonoideae, Gileae, Hydrophyllaceae
Hydrophyllaceae
Hydrophylloideae is a subfamily of the Boraginaceae family of flowering plants. Their taxonomic position is somewhat uncertain. Traditionally, and under the Cronquist system, they were given family rank under the name Hydrophyllaceae, and treated as part of the order Solanales...
, Limnanthaceae
Limnanthaceae
Limnanthaceae are a small family of annual herbs occurring throughout temperate North America. There are eight species and nineteen taxa currently recognized. Members of this family are prominent in vernal pool communities of California. Some taxa have been domesticated for use as an oil seed crop...
, Lotus
Lotus (genus)
Lotus is a genus that includes bird's-foot trefoils and deervetches and contains many dozens of species distributed world-wide. Depending on the taxonomic authority, roughly between 70 and 150 are accepted. Lotus is a genus of legume and its members are adapted to a wide range of habitats, from...
, Madiinae, Mimulus
Mimulus
Mimulus is a diverse plant genus, the monkey-flowers and musk-flowers. The about 150 species are currently placed in the family Phrymaceae. The genus has traditionally been placed in Scrophulariaceae. The removal of Mimulus from that family has been supported by studies of chloroplast DNA first...
, Onagreae, Epilobieae, Orcuttieae, Eschscholzioideae, Platystemonoideae, Astragalus
Astragalus
Astragalus is a large genus of about 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae, subfamily Faboideae. The genus is native to temperate regions of the Northern Hemisphere...
and Cupressus
Cupressus
The genus Cupressus is one of several genera within the family Cupressaceae that have the common name cypress; for the others, see cypress. It is considered a polyphyletic group...
have a principal center of diversity within the province. The flora of the Californian Province is partially shared with the spatially distant Chile-Patagonian Region of the Antarctic Kingdom and to a lesser extent Mediterranean Region of the Holarctic Kingdom. The vegetation of the Californian Province is varied. Wetter northern parts of the Californian Province (Northern California
Northern California
Northern California is the northern portion of the U.S. state of California. The San Francisco Bay Area , and Sacramento as well as its metropolitan area are the main population centers...
and Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
) as defined by Peter Raven and D.I. Axelrod, as well as by Conservation International
Conservation International
Conservation International is a nonprofit organization headquartered in Arlington, Virginia, which seeks to ensure the health of humanity by protecting Earth's ecosystems and biodiversity. CI’s work focuses on six key initiatives that affect human well-being: climate, food security, freshwater...
, fall under the Rocky Mountain Region
Rocky Mountain Region
The Rocky Mountain Floristic Region, also known as the Rocky Mountain Floristic Province, is a floristic region within the Holarctic Kingdom in western North America delineated by Armen Takhtajan and Robert F...
in Takhtajan and Thorne's system and don't make parts of the Madrean Region.
Sonoran Province
The Sonoran Province comprises arid areas in the southwestern U.S. and northwestern Mexico from CaliforniaCalifornia
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
and Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
to Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
and Tamaulipas
Tamaulipas
Tamaulipas officially Estado Libre y Soberano de Tamaulipas is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 43 municipalities and its capital city is Ciudad Victoria. The capital city was named after Guadalupe Victoria, the...
, including the Mojave
Mojave Desert
The Mojave Desert occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona, in the United States...
(characterized by Yucca brevifolia, Joshua Tree), Sonora and Chihuahua Deserts. The vegetation is dominated by Yucca
Yucca
Yucca is a genus of perennial shrubs and trees in the family Asparagaceae, subfamily Agavoideae. Its 40-50 species are notable for their rosettes of evergreen, tough, sword-shaped leaves and large terminal panicles of white or whitish flowers. They are native to the hot and dry parts of North...
, Cactaceae species (Opuntia
Opuntia
Opuntia, also known as nopales or paddle cactus , is a genus in the cactus family, Cactaceae.Currently, only prickly pears are included in this genus of about 200 species distributed throughout most of the Americas. Chollas are now separated into the genus Cylindropuntia, which some still consider...
spp. and other), as well as by Larrea tridentata (Creosote bush).
Mexican Highlands Province
The Mexican Highlands Province comprises areas in the Mexican PlateauMexican Plateau
The Central Mexican Plateau, also known as the Mexican Altiplano or Altiplanicie Mexicana, is a large arid-to-semiarid plateau that occupies much of northern and central Mexico...
region, including Madrean pine-oak woodlands
Madrean pine-oak woodlands
The Madrean pine-oak woodlands are subtropical woodlands found in the mountains of Mexico and the southwestern United States.The Madrean pine-oak woodlands are found at higher elevations in Mexico's major mountain ranges, the Sierra Madre Occidental, the Sierra Madre Oriental, the Trans-Mexican...
.
See also
- Madrean Sky IslandsMadrean sky islandsThe Madrean Sky Islands are enclaves of Madrean pine-oak woodlands, found at higher elevations in a complex of small mountain ranges in southern and southeastern Arizona, southwestern New Mexico, and northwestern Mexico. The sky islands are surrounded at lower elevations by the Sonoran and...
- Category: Madrean Sky Islands mountain ranges