Dipentodon is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Dipentodontaceae ''Dipentodontaceae'' is a family of flowering plants containing two genera. # ''Dipentodon'' Dunn - southern China, Assam, Myanmar # ''Perrottetia'' Kunth in F.W.H.von Humboldt - southern China, Southeast Asia, Papuasia, Queensland, Hawaii, Lati ...

. Its only

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

, ''Dipentodon sinicus'', is a small,

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, aft ...

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, including only woody plants with secondary growth, plants that are ...

native to southern China, northern Myanmar, and northern India.Jinshuang Ma and Bruce Bartholomew. 2008. "Dipentodontaceae" pages 494-495. In: Zhengyi Wu, Peter H. Raven, and Deyuan Hong (editors). ''Flora of China'' volume 11. Science Press: Beijing, China; Missouri Botanical Garden Press: St. Louis, Missouri, USA. It has been little studied and until recently its affinities remained obscure.

Description

''Dipentodon sinicus'' is a small, deciduous tree. The leaves are stipulate,

alternate Alternative or alternate may refer to: Arts, entertainment and media * Alternative (''Kamen Rider''), a character in the Japanese TV series ''Kamen Rider Ryuki'' * ''The Alternative'' (film), a 1978 Australian television film * ''The Alternative ...

, and

simple Simple or SIMPLE may refer to: *Simplicity, the state or quality of being simple Arts and entertainment * ''Simple'' (album), by Andy Yorke, 2008, and its title track * "Simple" (Florida Georgia Line song), 2018 * "Simple", a song by Johnn ...

, with

serrate Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied pr ...

margins. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is variable in form, usually an abbreviated,

umbel In botany, an umbel is an inflorescence that consists of a number of short flower stalks (called pedicels) that spread from a common point, somewhat like umbrella ribs. The word was coined in botanical usage in the 1590s, from Latin ''umbella'' "p ...

liform cyme containing 25 to 30 small 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 ...

and yellowish green. The

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 The term ''sepalum'' was coined b ...

s and

petal Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...

s are only weakly differentiated, usually 5, rarely to 7 in number, free, or united only at the base. The

hypanthium In angiosperms, a hypanthium or floral cup is a structure where basal portions of the calyx, the corolla, and the stamens form a cup-shaped tube. It is sometimes called a floral tube, a term that is also used for corolla tube and calyx tube. It ...

is very short or else the

ovary The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. ...

is superior. The

nectar Nectar is a sugar-rich liquid produced by plants in glands called nectaries or nectarines, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists ...

y disk is intrastaminal. The

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s are opposite the sepals. The ovary consists of three united

carpel Gynoecium (; ) 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 of a flower; it consists of (one or more) ''pistils'' ...

s with two

ovule In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the ''integument'', forming its outer layer, the ''nucellus'' (or remnant of the megasporangium), and the fe ...

s per carpel. The ovary is 1-loculate, but partly 3-loculate at its base. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is a 1-seeded

drupaceous In botany, a drupe (or stone fruit) is an indehiscent fruit in which an outer fleshy part (exocarp, or skin, and mesocarp, or flesh) surrounds a single shell (the ''pit'', ''stone'', or ''pyrena'') of hardened endocarp with a seed (''kernel'') ...

capsule.

History

''Dipentodon'' was named and first described in 1911 by

Stephen Troyte Dunn Stephen Troyte Dunn (26 August 1868, Bristol - 18 April, 1938, Sheen, Surrey, England) was a British botanist. He described and systematized a significant number of plants around the world, his input most noticeable in the taxonomy of the flora ...

in what is now called the

Kew Bulletin The ''Kew Bulletin'' is a quarterly peer-reviewed scientific journal on plant and fungal taxonomy and conservation published by Springer Science+Business Media on behalf of the Royal Botanic Gardens, Kew. Articles on palynology, cytology, anatomy, ...

. At that time, Dunn wrote: ''Dipentodon'' was placed in its own family by

Elmer Drew Merrill Elmer Drew Merrill (October 15, 1876 – February 25, 1956) was an American botanist and taxonomist. He spent more than twenty years in the Philippines where he became a recognized authority on the flora of the Asia-Pacific region. Through t ...

in 1941, but this placement was not generally followed. Instead, most authors put ''Dipentodon'' in the ill-defined and heterogeneous family

Flacourtiaceae The Flacourtiaceae is a defunct family of flowering plants whose former members have been scattered to various families, mostly to the Achariaceae and Salicaceae. It was so vaguely defined that hardly anything seemed out of place there and it beca ...

. In the twenty-first century, Flacourtiaceae is recognized by only a few

taxonomists In biology, taxonomy () is the scientific study of naming, defining ( circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are given ...

,Sue Zmarzty et alii. (in press). "Salicaceae" In: ''The Families and Genera of Vascular Plants''. Springer-Verlag: Berlin;Heidelberg, Germany. and then only in a much narrower

sense A sense is a biological system used by an organism for sensation, the process of gathering information about the world through the detection of Stimulus (physiology), stimuli. (For example, in the human body, the brain which is part of the cen ...

than it had been. ''Dipentodon'' is unrelated to Flacourtiaceae

sensu stricto ''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular co ...

, a segregate of

Salicaceae The Salicaceae is the willow family of flowering plants. The traditional family (Salicaceae ''sensu stricto'') included the willows, poplar, aspen, and cottonwoods. Genetic studies summarized by the Angiosperm Phylogeny Group (APG) have greatly ...

Molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

studies have led to the widespread acceptance of the family Dipentodontaceae and its placement in the order

Huerteales Huerteales is the botanical name for an order of flowering plants.Peter F. Stevens (2001 onwards). "Huerteales". In: Angiosperm Phylogeny Website. In: Missouri Botanical Garden Website. (see ''External links'' below) It is one of the 17 orders th ...

. Some authors have defined the family as consisting only of ''Dipentodon''.Vernon H. Heywood, Richard K. Brummitt, Ole Seberg, and Alastair Culham. ''Flowering Plant Families of the World''. Firefly Books: Ontario, Canada. (2007). . Others, following the recommendation of a 2006

study Study or studies may refer to: General * Education **Higher education * Clinical trial * Experiment * Observational study * Research * Study skills, abilities and approaches applied to learning Other * Study (art), a drawing or series of drawi ...

, have included ''Perrottetia''.Peter F. Stevens (2001 onwards). "Huerteales". In: Angiosperm Phylogeny Website. In: Missouri Botanical Garden Website. (see ''External links'' below) When the

APG II The APG II system (Angiosperm Phylogeny Group II system) of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Gr ...

classification was published in 2003, the taxonomic position of ''Dipentodon'' was still unknown and it was placed

incertae sedis ' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...

in the

angiosperms Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

. It was listed in the appendix under ''TAXA OF UNCERTAIN POSITION''.

References

External links

Huerteales
At

At
Missouri Botanical Garden Website
{{Taxonbar, from=Q13058684 Dipentodontaceae Least concern plants Trees of China Flora of Assam (region) Flora of Myanmar Monotypic rosid genera