The Magnoliaceae () are a

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

family, the magnolia family, in the order Magnoliales. It consists of two

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

: '' Magnolia'' and ''

Liriodendron ''Liriodendron'' () is a genus of two species of characteristically large trees, deciduous tree, deciduous over most of their populations, in the magnolia family (biology), family (Magnoliaceae). These trees are widely known by the common name ...

'' (tulip trees). Unlike most angiosperms, whose

flower 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 ...

parts are in whorls (rings), the Magnoliaceae have their

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s and

pistils Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl (botany), whorl of a flower; it consists ...

in spirals on a conical receptacle. This arrangement is found in some fossil plants and is believed to be a basal or early condition for angiosperms. The flowers also have parts not distinctly differentiated into

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s and

petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...

s, while angiosperms that evolved later tend to have distinctly differentiated sepals and petals. The poorly differentiated

perianth The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower. It is a structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepal ...

parts that occupy both positions are known as tepals. The family has about 219 species and ranges across

subtropical The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones immediately to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Ge ...

eastern

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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

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 ...

, the

West Indies The West Indies is an island subregion of the Americas, surrounded by the Atlantic Ocean, North Atlantic Ocean and the Caribbean Sea, which comprises 13 independent island country, island countries and 19 dependent territory, dependencies in thr ...

, tropical

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 ...

, southern and eastern

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Sri Lanka Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...

Indochina Mainland Southeast Asia (historically known as Indochina and the Indochinese Peninsula) is the continental portion of Southeast Asia. It lies east of the Indian subcontinent and south of Mainland China and is bordered by the Indian Ocean to th ...

Malesia Malesia is a biogeographical region straddling the Equator and the boundaries of the Indomalayan and Australasian realms. It is a phytogeographical floristic region in the Paleotropical kingdom. It was first recognized as a distinct region ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

, and

Korea Korea is a peninsular region in East Asia consisting of the Korean Peninsula, Jeju Island, and smaller islands. Since the end of World War II in 1945, it has been politically Division of Korea, divided at or near the 38th parallel north, 3 ...

Genera

The number of genera in Magnoliaceae is a subject of debate. Up to 17 have been recognized, including ''Alcimandra'', ''Lirianthe'', ''Manglietia'', ''Michelia'', ''Pachylarnax'', ''Parakmeria'', ''Talauma'' and ''Yulania''. However, many recent studies have opted to merge all genera within subfamily Magnolioideae into the genus ''Magnolia''. Thus, Magnoliaceae would include only two extant genera, ''Magnolia'' and ''Liriodendron''.

Description

The

monophyly 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 comm ...

of Magnoliaceae is supported by a number of shared morphological characters among the various genera in the family. Most have bisexual flowers (with the exception of ''Kmeria'' and some species of ''Magnolia'' section ''Gynopodium''), showy, fragrant, radial, and with an elongated receptacle. Leaves are alternate, simple, and sometimes lobed. 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 a solitary, showy flower with indistinguishable petals and sepals.

Sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s range from six to many; stamens are numerous and feature short filaments which are poorly differentiated from the anthers. Carpels are usually numerous, distinct, and on an elongated receptacle or torus. The fruit is an aggregate fruit (etaerio) of follicles which usually become closely appressed as they mature and open along the abaxial surface. Seeds have a fleshy coat,

aril An aril (), also called arillus, is a specialized outgrowth from a seed that partly or completely covers the seed. An arillode, or false aril, is sometimes distinguished: whereas an aril grows from the attachment point of the seed to the ova ...

, and color that ranges from red to orange (except ''Liriodendron''). Magnoliaceae flowers are

beetle Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

pollinated, except for ''Liriodendron'', which is bee pollinated. The carpels of'' Magnolia'' flowers are especially thick to avoid damage by beetles that land, crawl, and feast on them. The seeds of Magnolioideae are bird-dispersed, while the seeds of ''Liriodendron'' are wind-dispersed.

Biogeography

Due to its great age, the geographical distribution of the Magnoliaceae has become disjunct or fragmented as a result of major geologic events such as

ice age An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages, and g ...

s, continental drift, and mountain formation. This distribution pattern has isolated some species, while keeping others in close contact. Extant species of the Magnoliaceae are widely distributed in temperate and tropical Asia from the

Himalayas The Himalayas, or Himalaya ( ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than list of h ...

to Japan and southwest through

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

and

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...

. Asia is home to about two-thirds of the species in Magnoliaceae, with the remainder of the family spread across the Americas with temperate species extending into southern

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

and tropical elements extending into

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

and the West Indies.

Systematics

Foundational Taxonomic and Systematics Research (18th-19th century)

The earliest botanical description of the Magnoliaceae as a family is in Antonii Laurentii de Jussieu's ''Genera Plantarum'', which describes eight genera included within the family (''Euryandra'', ''Drymis'', Illicium, ''Michelia'', ''Magnolia'', ''Talauma, Liriodendrum'', and ''Mayna'') as well as four genera closely related to the family (''Dillenia'', ''Curatella'', ''Ochna'', and ''Quassia''). Bentham and Hooker's ''Genera Plantarum'', almost a century later, sorts the family's genera into three tribes: the Wintereae, including the genera ''Drimys'' and ''Illicium'', the Magnolieae, including the genera ''Talauma, Magnolia, Manglieta, Michelia'', and ''Liriodendron'', and the Schizandreae, including the genera ''Schizandra'' and ''Kadsura''. In his following work ''Adansonia'', Baillon recognizes Bentham and Hooker's changes and additions but proposes an alternative taxonomy where he sets aside the ''Tulipier'' genus and include all remaining genera under one Magnolieae tribe. From this basic separation, scholars have continued to debate the systematics of the family.

Modern Systematics Research (20th-21st century)

Dandy's taxonomic proposal in 1927 sets aside the genus ''Liriodendron'' as a part of the subfamily Liriodendreae and includes Bentham and Hooker's four genera in addition to four more (''Kmeria, Pachylarnax, Alcimandra'', and ''Elmerrillia'') within the Magnolieae tribe. Dandy's model with eleven genera was widely accepted until molecular evidence brought it into question (Figlar, 2019). Qiu et al. analyzed molecular data in 1995 to investigate the divergences within and between East Asian and East North American species of ''Magnolia'', presenting molecular evidence which shows that Dandy's section ''Rytidospermum'' is not monophyletic. Azuma et al. employ both molecular phylogeny and parsimonious mapping of the chemistry of floral scents in 1999 to propose a phylogenetic tree where, unlike Dandy's taxonomy, they include ''Michelia'' species within the ''Magnolia'' genus as a sister group to the subgenus ''Yulania'' and also find that the section ''Rytidospermum'' is not monophyletic, placing some of its members in a clade with the section ''Oyama''. The most recent research on the family continues the debate over the genera of the family. Wang et al.'s study analyzes complete chloroplast genome sequences of 86 species in the Magnoliaceae and supports a phylogeny with fifteen major clades, two subfamilies, two genera, and fifteen sections, maintaining ''Magnolias classification as one monophyletic genus. Dong et al. also place ''Magnolia'' as the sole genus of the subfamily Magnolioideae made up of fifteen sections. However, Yang et al. and Zhao et al. work with phylogenies of the Magnoliaceae that recognize several genera in the Magnolioideae.

Consensus and Debates Today

Although phylogenetic trees of the Magnoliaceae still include anywhere from 2 to 17 genera, the broad generic concept (where one genus, ''Magnolia'', is in the Magnolioideae) is largely accepted as a practical construction upheld by molecular and morphological evidence. Even as debates over rank persist, monophyletic groups are largely established with opportunities for further research into endangered and extinct species. The family's place as early angiosperms means that research into its taxonomy and evolutionary history contributes to our broader understanding of the evolution of plant life. The development of

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

sequencing at the end of the 20th century had a profound impact on the research of phylogenetic relationships within the family. The employment of ''ndh''F and cpDNA sequences has refuted many of the traditionally accepted phylogenetic relationships within the Magnoliaceae. For example, the genera ''Magnolia'' and ''Michelia'' were shown to be

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

when the remaining four genera of the Magnolioideae are split out. In fact, even many of the subgenera (''Magnolia'' subg. ''Magnolia'', ''Magnolia'' subg. ''Talauma'') have been found to be paraphyletic. Although no completely resolved

phylogeny A phylogenetic tree or phylogeny is a graphical representation which shows the evolutionary history between a set of species or Taxon, taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, M ...

for the family has yet been determined, these technological advances have allowed systematists to broadly circumscribe major lineages.

Economic significance

As a whole, the Magnoliaceae are not an economically significant family. With the exception of ornamental cultivation, the economic significance of magnolias is generally confined to the use of wood from certain timber species and the use of bark and flowers from several species believed to possess medicinal qualities. The wood of the American tuliptree, '' Liriodendron tulipifera'' and the wood of the cucumbertree magnolia, '' Magnolia acuminata'', and, to a lesser degree, that of the Frasier magnolia, '' Magnolia fraseri'', are harvested and marketed collectively as "yellow poplar." This is a lightweight and exceptionally fine-grained wood, lending itself to precision woodworking for purposes such as

pipe organ The pipe organ is a musical instrument that produces sound by driving pressurised air (called ''wind'') through the organ pipes selected from a Musical keyboard, keyboard. Because each pipe produces a single tone and pitch, the pipes are provide ...

building. Magnolias have a rich cultural tradition in China, where references to their healing qualities go back thousands of years. The Chinese have long used the bark of '' Magnolia officinalis'', a magnolia native to the mountains of China with large leaves and fragrant white flowers, as a remedy for cramps, abdominal pain, nausea, diarrhea, and indigestion. Certain magnolia flowers, such as the buds of '' Magnolia liliiflora'', have been used to treat chronic respiratory and sinus infections and lung congestion. Recently, magnolia bark has become incorporated into alternative medicine in the west, where tablets made from the bark of ''M. officinalis'' have been marketed as an aid for anxiety, allergies, asthma, and weight loss. Compounds found in magnolia bark might have antibacterial and antifungal properties, but no large-scale study on the health effects of magnolia bark or flowers has yet been conducted.

References

* Hunt, D. (ed). 1998. ''Magnolias and their allies''. International Dendrology Society & Magnolia Society.