The
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 ...
''Helwingia'' consists of
shrub
A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...
s or rarely small trees native to eastern
Asia
Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...
, 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 planet's highest peaks, including the very highest, Mount Everest. Over 100 ...
, and northern
Indochina
Mainland Southeast Asia, also known as the Indochinese Peninsula or Indochina, 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 the west an ...
. It is the only genus 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 ...
Helwingiaceae.
[Kew World Checklist of Selected Plant Families]
/ref>
Description
The plants have alternate, evergreen or deciduous leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...
and small 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 ...
s that are epiphyllous (growing from the leaf surface). During development, the flowers appear separate from the leaves, but eventually fuse with the leaf midrib. Flowers are small and yellow-green or purple, followed by red or black berries. Plants are dioecious
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproductio ...
.
Epiphyllous inflorescences
This trait is rather unusual among plants. This strange floral position upon a leaf is believed to be an adaption to insect pollination. Pollinators, which are too large for the flowers, land on the leaf surfaces and can pollinate the flowers, which would not be able to support the pollinators themselves.
Taxonomy
The APG II classification (2003) places them in the order Aquifoliales
The Aquifoliales are an order of flowering plants, including the Aquifoliaceae (holly) family, and also the Helwingiaceae (2-5 species of temperate Asian shrubs) and the Phyllonomaceae (4 species of Central American trees and shrubs). In 2001, th ...
, along with the hollies
The Hollies are a British pop rock band, formed in 1962. One of the leading British groups of the 1960s and into the mid-1970s, they are known for their distinctive three-part vocal harmony style. Allan Clarke and Graham Nash founded the band ...
and Phyllonomaceae
''Phyllonoma'' is a genus consisting of 4 species of trees and shrubs. ''Phyllonoma'' is the sole genus in the family Phyllonomaceae (an alternative name for the family is Dulongiaceae). ''Phyllonoma'' species are native to South and Central Amer ...
, which also has epiphyllous flowers.
The family Helwingiaceae does not exist in the
Cronquist classification (1981), which places this genus in the Cornaceae
The Cornaceae are a cosmopolitan family of flowering plants in the order Cornales. The family contains approximately 85 species in two genera, ''Alangium'' and ''Cornus''. They are mostly trees and shrubs, which may be deciduous or evergreen, alt ...
(dogwood family). ''Helwingia'' has also previously been placed in the Araliaceae
The Araliaceae are a family of flowering plants composed of about 43 genera and around 1500 species consisting of primarily woody plants and some herbaceous plants. The morphology of Araliaceae varies widely, but it is predominantly distinguisha ...
(ginseng family).
The family is named for botanist Georg Andreas Helwing
Georg Andreas Helwing ( pl, Jerzy Andrzej Helwing) (14 December 1666 – 3 January 1748) was a botanist and Lutheran pastor.
Helwing was born in Angerburg (Węgorzewo) in Brandenburg-Prussia's Duchy of Prussia. He became a "remote member" of t ...
.
Species
Species adapted from the World Checklist of Selected Plant Families
The World Checklist of Selected Plant Families (usually abbreviated to WCSP) is an "international collaborative programme that provides the latest peer reviewed and published opinions on the accepted scientific names and synonyms of selected plan ...
:[
# '']Helwingia chinensis
''Helwingia chinensis'' is a plant species first described by Alexander Theodorowicz Batalin. ''Helwingia chinensis'' is part of the genus ''Helwingia'' and the family Helwingiaceae
The genus ''Helwingia'' consists of shrubs or rarely small tr ...
'' Batalin - Thailand, Myanmar, China: Gansu, Guizhou, Hubei, Hunan, Shaanxi, Sichuan, Tibet, Yunnan
# ''Helwingia himalaica
The genus ''Helwingia'' consists of shrubs or rarely small trees native to eastern Asia, the Himalayas, and northern Indochina. It is the only genus in the family Helwingiaceae.
Description
The plants have alternate, evergreen or deciduous leave ...
'' Hook.f. & Thomson ex C.B.Clarke - Thailand, Myanmar, Bhutan, Nepal, India: Assam, Sikkim, China: Tibet, Chongqing, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Sichuan, Yunnan
# ''Helwingia japonica
''Helwingia japonica'', the Japanese helwingia, is a species of ''Helwingia'' native to East Asia. ''Helwingia japonica'' is part of the genus ''Helwingia'' and the family Helwingiaceae.
Description
Helwingia japonica is a dioecious shrub wh ...
'' (Thunb.) F.Dietr. - Japan (incl. Ryukyu Islands), Korea, Taiwan, Myanmar, Bhutan, Vietnam, India: Assam, Sikkim, China: Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Shandong, Shanxi, Sichuan, Yunnan, Zhejiang
# ''Helwingia omeiensis
The genus ''Helwingia'' consists of shrubs or rarely small trees native to eastern Asia, the Himalayas, and northern Indochina. It is the only genus in the family Helwingiaceae.
Description
The plants have alternate, evergreen or deciduous leave ...
'' (W.P.Fang) H.Hara & S.Kuros. - China: Gansu, Guangxi, Guizhou, Hubei, Hunan, Shaanxi, Sichuan, Yunnan
References
External links
Aquifoliales - Angiosperm Phylogeny Website
consulted 2007-01-26.
, Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 29 July 2006.
** Also se
Helwingiaceae
from ''NCBI-Taxonomy''
Helwingiaceae
USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN Online Database). National Germplasm Resources Laboratory, Beltsville, Maryland. Consulted 2007-01-26.
{{Taxonbar, from1=Q132079, from2=Q11862231
Aquifoliales
Asterid genera
Dioecious plants