''Maianthemum'' includes the former genus ''Smilacina'' and is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of ...

flowering plants with fleshy, persistent

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. It is widespread across much of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

and

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

,Kew World Checklist of Selected Plant Families
/ref>Flora of China, Vol. 24 Page 217, 舞鹤草属 wu he cao shu, ''Maianthemum'' F. H. Wiggers, Prim. Fl. Holsat. 14. 1780.
/ref>Flora of North America, Vol. 26 Page 206, ''Maianthemum'' F. H. Wiggers, Prim. Fl. Holsat. 14. 1780.
/ref> and may be terrestrial, aquatic or

epiphytic An epiphyte is a plant or plant-like organism that grows on the surface of another plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphyt ...

. It is characterized by simple, unbranched stems that are upright, leaning or hanging down and have 2–17 foliage leaves. Leaves are simple and may clasp the stem or be short- petiolate. 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 terminal and either a

panicle In botany, a panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a p ...

or a

raceme A raceme () or racemoid is an unbranched, indeterminate growth, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are ...

with few to many pedicelate flowers. Most

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

have 6

tepals A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of ve ...

and 6

stamens 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 filamen ...

; a few have parts in 4s. Tepals are distinct in most species and all of similar size. Flowers are spreading, cup-shaped or bell-shaped and usually white, but lavender to red or green in some species. Fruits are rounded to lobed berries containing few to several seeds.

Vegetative

; Rhizomes and roots Rhizomes are persistent and have scale leaves. They can be

sympodial In botany, sympodial growth is a bifurcating branching pattern where one branch develops more strongly than the other, resulting in the stronger branches forming the primary shoot and the weaker branches appearing laterally. A sympodium, als ...

; spreading and thread-like, or cylindric, clumped and fleshy. '' Maianthemum paludicola'' has an unusual woody, upright sympodial rhizome set above ground. Roots may be spread along the rhizome, clumped at the nodes, or clumped near the base of leafy shoots. The rhizome is the perennial part of the plant and growth is by branching of the rhizome. Flowering/fruiting shoots are attached to the rhizome by a discreet internode, are short-lived and wither at the end of the growing season. ; Stems and leaves The stems are unbranched and pendant to arching or upright. Fertile plants have 2 to 17 or more stem (cauline)

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, ...

(arising from the stem) that are alternate along the stem. Most species produce fertile shoots seasonally. A few species such as '' Maianthemum canadense'' and '' Maianthemum dilatatum'' also have a vegetative phase, producing a solitary leaf on sterile shoots; plants may continue in this vegetative phase for up to six years. '' Maianthemum trifolium'' produces two petiolate foliage leaves the first year, then a flowering shoot the second year with 2-4 sessile leaves. In most species, leaves have a large midvein, dividing the leaves in half, then each half is again divided by a slightly smaller vein; each quarter again divided by progressively finer veins. The resulting pattern is that the leaves have three prominent veins, and adjacent veins are of different diameters. A few species, such as '' Maianthemum stellatum'', have leaves with veins that are often all of roughly the same diameter. Leaf edges may be flat or wavy (undulate) and sometimes have small, outward-pointing teeth.

Reproductive

; Inflorescence The

is either a

or a

with few to many pedicellate flowers. Racemes may be simple (one flower per node) or complex (some nodes with 2 or more flowers). Panicles may be few- to many-branched and the branches themselves are often racemose. A few Asian species such as '' Maianthemum henryi'' have a main axis with fully extended racemose branches at lower nodes and upper nodes with clustered flowers. The type and pattern of inflorescence is the most useful feature to separate ''Maianthemum'' species. ; Flowers The flowers are

actinomorphic Floral symmetry describes whether, and how, a flower, in particular its perianth, can be divided into two or more identical or mirror-image parts. Uncommonly, flowers may have no axis of symmetry at all, typically because their parts are spirall ...

(radially symmetric) and relatively small. The

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 ...

in most species has six

, in two whorls of three ( trimerous). '' Maianthemum canadense, Maianthemum dilatatum'', and '' Maianthemum bifolium'' however are dimerous, with 4-tepaled flowers. Tepals are greenish, or white to pink or mauve in most species, but are a deep purple in '' Maianthemum purpureum'' and may have purple spots in '' Maianthemum gigas var. gigas''. The tepals in most species are free (not fused), all of a similar size and flowers are spreading to cup-shaped. Some Asian species such as ''Maianthemum henryi'' have bell-shaped (campanulate) flowers with partially fused tepals. The flowers are usually

bisexual Bisexuality is romantic attraction, sexual attraction, or sexual behavior toward both males and females. It may also be defined as the attraction to more than one gender, to people of both the same and different gender, or the attraction t ...

, containing both male (

androecium 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 ...

) and female (

gynoecium 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 ...

) parts, although two species from Japan, '' Maianthemum hondoense'' and '' Maianthemum yesoense'', are reported to be

unisexual Dioecy ( ; ; adj. dioecious, ) is a characteristic of certain species that have distinct unisexual individuals, each producing either male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is ...

. ; Gynoecium The

ovaries The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are endocr ...

are superior (attached above the other floral parts) and are spherical to cylindrical. The

pistil 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 ...

has two or three carpels separated by walls with nectar-carrying canals.

Style Style, or styles may refer to: Film and television * ''Style'' (2001 film), a Hindi film starring Sharman Joshi, Riya Sen, Sahil Khan and Shilpi Mudgal * ''Style'' (2002 film), a Tamil drama film * ''Style'' (2004 film), a Burmese film * '' ...

s are narrow (< 5mm wide) and about as long as the ovary. Stigmas are lobed and slightly wider than the style. ; Androecium

Stamens 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 filamen ...

are 4 or 6 and usually inserted at the base of the tepals, but may be inserted about 1 mm above, as in '' Maianthemum flexuosum''. Anthers are cylindrical and split longitudinally. ; Fruit and seeds The

berry A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit although many pips or seeds may be present. Common examples of berries in the cul ...

is globose and often lobed. Berries ripen to red. In most species unripe berries are green or green mottled with red or copper. In some, e.g. '' Maianthemum stellatum'' the immature berries have dark stipes. The

seeds In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be sown, which may include seed and husk or tuber. Seeds are the ...

are usually few and spherical but in some species may be conical.

Morphology

file:Maianthemum stellatum rhizomes.jpg, Rhizome and roots: ''M. stellatum'' file:Maianthemum racemosum amplexicaule blooming plant.jpg, Unbranched, upright stem: ''M. racemosum amplexicaule'' file:Maianthemum canadense sterile plants.jpg, Sterile plants: ''M. canadense'' file:Maianthemum stellatum 15290.JPG, Simple raceme; one pedicellate flower per node: ''M. stellatum'' file:Flower buds close up Maianthemum canadense.jpg, Complex raceme, some nodes with 2 flowers: ''M. canadense'' file:Maian amplex panicle.jpg, Panicle with main axis and side branches: ''M. racemosum amplexicaule''

Taxonomy

The current concept includes species that were previously divided into 2 closely related genera; ''Maianthemum'', including dimerous species and ''Smilacina'' for the trimerous ones. Studies in the 1970s showed strong genetic similarity, similar fruits, and evidence that the 4-tepal species evolved from a 6-tepal species, so the genus ''Smilacina'' was combined with ''Maianthemum''.

Phylogeny

In the APG III classification system, ''Maianthemum'' is placed in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Asparagaceae Asparagaceae (), known as the asparagus family, is a family of flowering plants, placed in the order Asparagales of the monocots. The family name is based on the edible garden asparagus, '' Asparagus officinalis''. This family includes both ...

, subfamily Nolinoideae (formerly the family Ruscaceae). Like many lilioid monocots, ''Maianthemum'' (including the former ''Smilacina'') were formerly included in the family

Liliaceae The lily family, Liliaceae, consists of about 15 genera and 610 species of flowering plants within the order Liliales. They are monocotyledonous, perennial, herbaceous, often bulbous geophytes. Plants in this family have evolved with a fai ...

. The genus has also been placed in the former family Convallariaceae, and resembles the closely related ''

Polygonatum ''Polygonatum'' , also known as King Solomon's-seal or Solomon's seal, is a genus of flowering plants. In the APG III classification system, it is placed in the family Asparagaceae, subfamily Nolinoideae (formerly the family Ruscaceae). It ha ...

'', hence the common name "false Solomon's seal".

Etymology

''Maianthemum'' comes from the Greek for "May" (maios) and “flower” (Anthos).

Distribution and habitat

The genus is widespread across much of

and

Ecology

The majority of species are spring-flowering forest herbs, requiring shaded, moist conditions and cool temperatures. Some however (e.g. '' Maianthemum monteverdense'') are epiphytes. Others such as '' Maianthemum stellatum'' grow in diverse habitats from sand dunes to forest under-stories. And '' Maianthemum trifolium'' and '' Maianthemum paludicola'' are found in full sun in open wetlands. ''M. trifolium'' is sometimes considered aquatic. The species that are forest herbs generally begin growth in early spring, with leaves expanding before the tree canopy fully develops. Epiphytic tropical species usually grow new shoots in the dry season.

Conservation

Many of the North American ''Maianthemum'' are widespread and relatively common. Several though are considered endemic to the wider “Mesomexico”. ''Maianthemum comaltepecense'' is a rare perennial, terrestrial herb found as an understory species in moist forests, known only from Oaxaca, Mexico,Espejo et al.1996. Maianthemum comaltepecense, Una Nueva Especie del Estado de Oaxaca. Acta Botánica Mexicana (1996), 36:21-28 and

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 southwest Mexico.

Species

Species accepted: #'' Maianthemum amoenum'' (H.L.Wendl.) LaFrankie – Honduras, El Salvador, Guatemala, Mexico (Chiapas, Oaxaca, Veracruz) # '' Maianthemum atropurpureum'' (Franch.) LaFrankie – Sichuan, Yunnan #'' Maianthemum bicolor'' (Nakai) Cubey – Korea # '' Maianthemum bifolium'' (L.) F.W.Schmidt – northern and central Europe and northern Asia from Spain to Kamchatka; China, Japan, Siberia, Kazakhstan, Germany, Italy, Ukraine, etc # '' Maianthemum canadense'' Desf. – St. Pierre and Miquelon, much of eastern USA and all provinces and territories in Canada except Nunavut #'' Maianthemum comaltepecense'' Espejo, López-Ferr. & Ceja – Mexico (Oaxaca) # '' Maianthemum dahuricum'' (Turcz. ex Fisch. & C.A.Mey.) LaFrankie – Siberia, Russian Far East, Manchuria, Inner Mongolia, Korea # '' Maianthemum dilatatum'' (Alph.Wood) A.Nelson & J.F.Macbr. – Mongolia, Korea, Japan, Russian Far East, Alaska, Yukon, British Columbia, Washington, Idaho, Oregon, California #'' Maianthemum flexuosum'' (Bertol.) LaFrankie – Mexico (Chiapas, Guerrero, Hidalgo, Michoacán, Oaxaca, Veracruz), El Salvador, Guatemala, Honduras, Nicaragua #'' Maianthemum formosanum'' (Hayata) LaFrankie – Taiwan # '' Maianthemum forrestii'' (W.W.Sm.) LaFrankie – Yunnan # '' Maianthemum fusciduliflorum'' (Kawano) S.C.Chen & Kawano – Tibet, Yunnan, Bhutan, Assam, Myanmar # '' Maianthemum fuscum'' (Wall.) LaFrankie – Nepal, Tibet, Yunnan, Bhutan, Assam, Myanmar #'' Maianthemum gigas'' (Woodson) LaFrankie – Mexico (Chiapas), Costa Rica, Guatemala, Panama, and Nicaragua # '' Maianthemum gongshanense'' (S.Yun Liang) H.Li – Yunnan # '' Maianthemum henryi'' (Baker) LaFrankie – Vietnam, Myanmar, Tibet, southern China #'' Maianthemum hondoense'' (Ohwi) LaFrankie – Honshu #'' Maianthemum × intermedium'' Vorosch. – Siberia, Russian Far East ''(M. bifolium × M. dilatatum)'' # '' Maianthemum japonicum'' (A.Gray) LaFrankie – Russian Far East, Japan, Korea, northeastern China # '' Maianthemum lichiangense'' (W.W.Sm.) LaFrankie – Gansu, Shaanxi, Sichuan, Yunnan #'' Maianthemum macrophyllum'' (M.Martens & Galeotti) LaFrankie – Mexico (Veracruz, Oaxaca) #'' Maianthemum mexicanum'' García Arév – Mexico (Durango, Sinaloa) #'' Maianthemum monteverdense'' LaFrankie – Nicaragua, Costa Rica # '' Maianthemum nanchuanense'' H.Li & J.L.Huang – Sichuan # '' Maianthemum oleraceum'' (Baker) LaFrankie – Nepal, Bhutan, Assam, Myanmar, Tibet, Sikkim, Guizhou, Sichuan, Yunnan #'' Maianthemum paludicola'' LaFrankie – Costa Rica # '' Maianthemum paniculatum'' (M.Martens & Galeotti) LaFrankie – Mexico (Chiapas, Guerrero, Hidalgo, Oaxaca, Puebla and Veracruz), Costa Rica, El Salvador, Guatemala, Honduras, and Panamá # '' Maianthemum purpureum'' (Wall.) LaFrankie – Tibet, Yunnan, Nepal, Bhutan, Sikkim, Assam (also called Himalayan Mayflower or Purple Mayflower) # '' Maianthemum racemosum'' (L.) Link – All USA states, all Canadian provinces and territories (except Nunavut and Labrador) and Mexico (Chihuahua) #'' Maianthemum robustum'' (Makino & Honda) LaFrankie – Honshu #'' Maianthemum salvinii'' (Baker) LaFrankie – Mexico (Chiapas), Guatemala #'' Maianthemum scilloideum'' (M.Martens & Galeotti) LaFrankie – Mexico (Chiapas, Coahuila, Guerrero, Michoacán, Nuevo León, Oaxaca, Puebla and Veracruz), Guatemala, Honduras # '' Maianthemum stellatum'' (L.) Link – Most states in USA (except those southeast of New Mexico), all Canadian provinces and territories (except Nunavut and Labrador) and in the Mexican states of Chihuahua, Coahuila, Nuevo León and Sonoroa; introduced in Norway, Sweden # '' Maianthemum stenolobum'' (Franch.) S.C.Chen & Kawano – Sichuan, Gansu, Hubei # '' Maianthemum szechuanicum'' (F.T.Wang & Tang) H.Li – Sichuan, Yunnan # '' Maianthemum tatsienense'' (Franch.) LaFrankie – Bhutan, Assam, Myanmar, Gansu, Guangxi, Guizhou, Hubei, Hunan, Sichuan, Yunnan # '' Maianthemum trifolium'' (L.) Sloboda – Siberia, Russian Far East to North Korea, St. Pierre and Miquelon, all Canadian provinces and territories, northeastern United States # '' Maianthemum tubiferum'' (Batalin) LaFrankie – Gansu, Hubei, Qinghai, Shaanxi, Sichuan #'' Maianthemum yesoense'' (Franch. & Sav.) LaFrankie – Japan

References

* {{Taxonbar, from=Q157848 Asparagaceae genera