Helwingia

{{Short description|Genus of flowering plants}} {{automatic taxobox |image = Helwingia japonica m.jpg |image_caption = Flowering ''Helwingia japonica'' var. ''japonica'' specimen |image2 = Helwingia japonica (fruits s4).jpg |image2_caption = Detail of epiphyllous ''Helwingia japonica'' fruit |parent_authority = Decne.<ref name=APGIII2009>{{Cite journal |last=Angiosperm Phylogeny Group |year=2009 |title=An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III |journal=Botanical Journal of the Linnean Society |volume=161 |issue=2 |pages=105–121 |doi=10.1111/j.1095-8339.2009.00996.x |doi-access=free |hdl=10654/18083 |hdl-access=free }}</ref> |taxon = Helwingia |authority = Willd. |range_map = Helwingia distribution.png |range_map_caption = Distribution of ''Helwingia '' }}

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'''.<ref name=k>[http://apps.kew.org/wcsp/namedetail.do?name_id=98036 Kew World Checklist of Selected Plant Families]{{Dead link|date=July 2024 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><ref>[http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=114973 Flora of China Vol. 14 Page 227 <big>青荚叶属</big> qing jia ye shu ''Helwingia'' Willdenow, Sp. Pl. 4: 634, 716. 1806, nom. cons., not ''Helvingia'' Adanson (1763). ]</ref>

==Description== The plants have alternate, evergreen or deciduous leaves and small inflorescences that are epiphyllous (growing from the leaf surface). During development, the flowers appear separate from the leaves,{{explain|date=March 2023}}, eventually fusing with the leaf midrib.<ref>{{Cite journal|last1=Dickinson|first1=Timothy A.|last2=Sattler|first2=Rolf|date=1975|title=Development of the Epiphyllous Inflorescence of Helwingia japonica (Helwingiaceae)|journal=American Journal of Botany|volume=62|issue=9|pages=962–973|doi=10.2307/2441641|jstor=2441641|issn=0002-9122}}</ref> Flowers are small and yellow-green or purple, followed by red or black berries. Plants are dioecious.<ref>{{cite journal|doi=10.1186/1756-0500-7-402|title=Biological pattern and transcriptomic exploration and phylogenetic analysis in the odd floral architecture tree: Helwingia willd|year=2014|last1=Sun|first1=Cheng|last2=Yu|first2=Guoliang|last3=Bao|first3=Manzhu|last4=Zheng|first4=Bo|last5=Ning|first5=Guogui|journal=BMC Research Notes|volume=7|page=402|pmid=24969969|pmc=4083144 |doi-access=free }}</ref> ===Epiphyllous inflorescences=== This trait is rather unusual among plants. This atypical floral position upon a leaf is believed to be an adaption to insect pollination. Pollinators which are too large to be supported by the floral pedicels, land on the leaf surface and can pollinate the flowers, which would not be able to support the pollinators on their own.<ref name = "Sun et al., 2014">{{cite journal | doi=10.1186/1756-0500-7-402 | title=Biological pattern and transcriptomic exploration and phylogenetic analysis in the odd floral architecture tree: Helwingia willd | year=2014 | last1=Sun | first1=Cheng | last2=Yu | first2=Guoliang | last3=Bao | first3=Manzhu | last4=Zheng | first4=Bo | last5=Ning | first5=Guogui | journal=BMC Research Notes | volume=7 | page=402 | pmid=24969969 | pmc=4083144 | doi-access=free }}</ref>

==Taxonomy== The APG II classification (2003) places them in the order Aquifoliales, along with the hollies and Phyllonomaceae, which also has epiphyllous flowers.<ref>{{Cite journal|last1=Dickinson|first1=T. A.|last2=Sattler|first2=R.|date=1974|title=Development of the epiphyllous inflorescence of Phyllonoma integerrima (Turcz.) Loes.: implications for comparative morphology*|journal=Botanical Journal of the Linnean Society|language=en|volume=69|issue=1|pages=1–13|doi=10.1111/j.1095-8339.1974.tb01609.x|issn=1095-8339}}</ref>

The family Helwingiaceae does not exist in the Cronquist classification (1981), which places this genus in the Cornaceae (dogwood family). ''Helwingia'' has also previously been placed in the Araliaceae (ginseng family).<ref>{{Cite journal|last1=Hara|first1=Hiroshi|last2=Kurosawa|first2=Sachiko|date=1975|editor-last=Ohashi|editor-first=H.|title=A Revision of the Genus Helwingia|url=http://umdb.um.u-tokyo.ac.jp/DKankoub/Bulletin/no08/no08022.html|journal=Flora of the Eastern Himalayas|volume=3|pages=393–413}}</ref>

The family is named for botanist Georg Andreas Helwing.<ref>{{Cite web|last=Hinkley|first=Daniel J.|date=1 May 2007|title=Helwingia|url=https://www.hortmag.com/.amp/plants/helwingia|website=Horticulture Magazine}}</ref>

==Species== Species adapted from the World Checklist of Selected Plant Families:<ref name=k/> * ''Helwingia chinensis'' Batalin - Thailand, Myanmar, China: Gansu, Guizhou, Hubei, Hunan, Shaanxi, Sichuan, Tibet, Yunnan * ''Helwingia himalaica'' 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'' (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'' (W.P.Fang) H.Hara & S.Kuros. - China: Gansu, Guangxi, Guizhou, Hubei, Hunan, Shaanxi, Sichuan, Yunnan

==References== {{Reflist}}

==External links== {{Commons category|Helwingia}} *[http://www.mobot.org/MOBOT/Research/APweb/orders/aquifolialesweb2.htm#Aquifoliales Aquifoliales - Angiosperm Phylogeny Website], consulted 2007-01-26. *[http://delta-intkey.com/angio/www/helwingi.htm Helwingiaceae] {{Webarchive|url=https://web.archive.org/web/20061101100852/http://delta-intkey.com/angio/www/helwingi.htm |date=2006-11-01 }}, Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 29 July 2006. ** Also see [http://delta-intkey.com/angio/www/cornacea.htm Cornaceae] {{Webarchive|url=https://web.archive.org/web/20070310223456/http://delta-intkey.com/angio/www/cornacea.htm |date=2007-03-10 }} *[https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?lin=s&p=has_linkout&id=42226 Helwingiaceae] from ''NCBI-Taxonomy'' *[https://web.archive.org/web/20081012154323/http://www.ars-grin.gov/cgi-bin/npgs/html/family.pl?524 Helwingiaceae], USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN Online Database). National Germplasm Resources Laboratory, Beltsville, Maryland. Consulted 2007-01-26.

Category:Aquifoliales Category:Asterid genera Category:Dioecious plants