arum
{{Short description|Genus of flowering plants in the family Araceae}}
{{Distinguish|Ara (genus)|Aurum (disambiguation){{!}}Aurum}}
{{Other uses}}
{{Automatic taxobox
| image = Arum palaestinum flower.jpg
| image_caption = Arum palaestinum
| display_parents = 2
| taxon = Arum
| authority = L.
| synonyms =
- Aron Adans.
- Gymnomesium Schott
| range_map = Arum distribution.svg
| range_map_caption = Range of the genus Arum
}}
Arums are flowering plants from the genus Arum in the Araceae family; they are native to Europe, northern Africa, and western and central Asia, with the highest species diversity in the Mediterranean region. {{cite book |last1=Govaerts |first1=R. |last2=Frodin |first2=D.G. |year=2002 |title=World Checklist and Bibliography of Araceae (and Acoraceae) |publisher=The Board of Trustees of the Royal Botanic Gardens, Kew |ISBN=9781842460368 }}{{page needed|date= March 2025 }} Frequently called arum lilies, they are not closely related to the true lilies Lilium. Plants in the closely related genus Zantedeschia are also called 'arum lilies'.
They are rhizomatous, herbaceous perennial plants growing to 20–60 cm tall, with sagittate (arrowhead-shaped) leaves 10–55 cm long. The flowers are produced in a spadix, surrounded by a 10–40 cm long, distinctively coloured spathe, which may be white, yellow, brown, or purple. Some species are scented, others not. The fruit is a cluster of bright orange or red berries.
All parts of the plants, including the berries, are poisonous as they contain needle-shaped crystals of calcium oxalate.Nelson, L. et al. (2007) Handbook of Poisonous and Injurious Plants. New York Botanical Garden. In spite of this, the plant has a history of culinary use among Arab peasants in Palestine who leached the toxins from the plant before the leaves were consumed.{{cite book|last=Ḳrispil|first=Nissim|author-link=|title=A Bag of Plants (The Useful Plants of Israel) |publisher=Cana Publishing House Ltd.|volume=3 (Ṭ.-M.) |year=1985|location=Jerusalem|pages=|language=he|isbn=965-264-011-5 |oclc=959573975 }}, s.v. Arum palaestinum ({{Script/Hebrew|לוף}}){{cite book |author-last=Dalman|author-first=Gustaf |author-link=Gustaf Dalman |title=Work and Customs in Palestine, volume II |publisher=Dar Al Nasher |location=Ramallah|year=2020 |volume=2 (Agriculture) |page=329 |language=en |translator=Robert Schick |editor=Nadia Abdulhadi-Sukhtian |isbn=978-9950-385-84-9 }}{{cite book |author-last1=Mayer-Chissick|author-first1=Uri|author-last2=Lev |author-first2=Efraim |editor-last1=Yaniv |editor-first1=Zohara |editor-last2=Dudai |editor-first2=Nati |contribution=Wild Edible Plants in Israel Tradition Versus Cultivation |title=Medicinal and Aromatic Plants of the Middle-East|publisher=Dordrecht: Springer |location=New York|year=2016 |pages=18–20 |language=en |oclc=1062304427|isbn=9789402406603}}
The genus name is the Latinized form of the Greek name for these plants, aron.
Inflorescence and pollination
File:Modell von Arum (Aronstab) -Brendel Nr. 202-.jpg.]]
The flowers are borne on a poker-shaped inflorescence called a spadix, which is partially enclosed in a spathe or leaf-like hood of varying colour. The flowers are hidden from sight, clustered at the base of the spadix with a ring of female flowers at the bottom and a ring of male flowers above them.
Above the male flowers is a ring of hairs forming an insect trap. The insects are trapped beneath the ring of hairs and are dusted with pollen by the male flowers before escaping and carrying the pollen to the spadices of other plants, where they pollinate the female flowers. Once the plant is pollinated, the small hairs wither away and the trapped insects are released.
After the inflorescence opens, the spadix heats up well above ambient temperature, due to a phenomenon called thermogenesis. This is caused by the rapid consumption of starch in cyanide insensitive respiration, which is biochemically different from the respiration normally found in plants. The heat is used to vaporize{{Clarify|reason=Vaporize or aerosolize or?|date=July 2020}} odour components, which in species with short "flower-stalks" cause a faecal smell. This in turn attracts the small flies and gnats that are to be trapped within the inflorescence. As the time required for successful pollination to occur can be several days, many of the small insects nevertheless die within the flower due to their short lifespan. Therefore, dead insects are frequently found within the inflorescence, when opened, sometimes leading the finder to believe it is a carnivorous plant – but that is not the case. No digestive enzymes or similar components are present; and in fact, once pollinated, the entire inflorescence starts withering except the central part, from which the berries later emerge.{{Cite book |last=Boyce|first=Peter |year=1993 |title=The Genus Arum |publication-place=London |publisher=HMSO |isbn=0-11-250085-4 }} pp. 35-40
Pollination-wise, the species of Arum can be split into two (or three) distinct groups. The "cryptic" species have the inflorescence on a relatively short stalk, and the odour released during the thermogenesis is recognizable to the human nose as distinctively faecal. These species are visited by insects with some relation to dung, such as owl-midges (Psychodidae) or fungus-gnats (Sciara). In northern Europe, only the cryptic-flowered species are found.
The other main group are called "flag" species, due to the inflorescence being on a long stalk. These species also exhibit thermogenesis, but if an odour is released it is not recognizable to the human nose, and it is debated if pollinators are attracted by a non-recognizable smell, the thermogenesis itself or visual attraction.
Finally the closely related A. idaeum and A. creticum does not seem to fit any of the two groups. A. creticum appears to be of the "flag" group but, as the only species, emits a pleasing lemony smell. The apparently "cryptic" A. idaeum does not emit a recognizable smell.
Species
File:Kozlaci na Vidovoj gori (Croatia).JPG
{{As of|2025|2}}, Plants of the World Online accepts the following 27 species and one hybrid:{{R|POWO}}
- Arum apulum {{small|(Carano) P.C.Boyce}} - Italy (Apulia)
- Arum besserianum {{small|Schott}} - South Poland, Ukraine
- Arum concinnatum {{small|Schott}} - South Greece, Turkey
- Arum creticum {{small|Boiss. & Heldr.}} - Crete, Turkey
- Arum cylindraceum {{small|Gasp.}} - Central Europe, Iberian Peninsula, Italy, Balkans, Turkey, Cyprus
- Arum cyrenaicum {{small|Hruby}} - Crete, Libya (Cyrenaica)
- Arum dioscoridis {{small|Sm.}} - East Aegean, Cyprus, Turkey, Levant
- Arum euxinum {{small|R.R.Mill}} - Turkey (Bithynia)
- Arum gratum {{small|Schott}} - Lebanon, Syria
- Arum hainesii {{small|Riedl}} - East Iraq
- Arum hygrophilum {{small|Boiss.}} - Turkey, Levant, Cyprus, Morocco
- Arum idaeum {{small|Coustur. & Gand.}} - Crete
- Arum italicum {{small|Mill.}} - Mediterranean Europe, Britain, Maghreb, Crimea, Caucasus, Turkey, Iraq
- Arum jacquemontii {{small|Blume}} - Iran, Afghanistan, South Central Asia, West Himalayas
- Arum korolkowii {{small|Regel}} - North Iran, Afghanistan, Central Asia
- Arum lucanum {{small|Cavara & Grande}} - South Italy, Albania
- Arum maculatum {{small|L.}} - Europe, Turkey, West Caucasus
- Arum megobrebi {{small|Lobin, M.Neumann, Bogner & P.C.Boyce}} - Transcaucasus, NE Turkey
- Arum meryemianum {{small|Yıldırım}} - Turkey
- Arum nigrum {{small|Schott}} - Greece, Montenegro
- Arum orientale {{small|M.Bieb.}} - Carpathian Basin, Carpathians, Balkans, Crimea, Donbass, Caucasus, Turkey, Levant
- Arum palaestinum {{small|Boiss.}} - Levant
- Arum pictum {{small|L.f.}} - Corsica, Sardinia, Balearics
- Arum purpureospathum {{small|P.C.Boyce}} - Crete
- Arum rupicola {{small|Boiss.}} - Lesbos, Turkey, Transcaucasus, Iran, Levant, Iraq
- Arum sintenisii {{small|(Engl.) P.C.Boyce}} - Cyprus, Turkey
- Arum × sooi {{small|Terpó}} - Hungary, Spain
- Arum taiwanianum {{small|S.S.Ying}} - Taiwan
Formerly placed here:
- Arum triphyllum {{small|L.}} – now Arisaema triphyllum {{small|(L.) Schott}}
- Arum dracunculus {{small|L.}} – now Dracunculus vulgaris {{small|Schott}}
Gallery
Arum concinnatum - Icones Aroidearum pl. 39 (1857).jpg|A. concinnatum
Arum italicum — Flora Batava — Volume v13.jpg|A. italicum
Arum maculatum — Flora Batava — Volume v14.jpg|A. maculatum
=Leaves=
Арум Бессера (Arum besserianum).jpg|A. besserianum
Arum concinnatum RF.jpg|A. concinnatum
Arum creticum, Crete 03(js).jpg|A. creticum
Arum cylindraceum1.JPG|A. cylindraceum
Arum dioscoridis, Jamiaa, Beirut, Lebanon (52261039630).jpg|A. dioscoridis
Arum hygrophilum kz2.jpg|A. hygrophilum
Arum idaeum RF.jpg|A. idaeum
Arum italicum subsp. italicum sl7.jpg|A. italicum
Arum korolkowii 38577675.jpg|A. korolkowii
Arum meryemianum.jpg|A. meryemianum
Arum nigrum 01.jpg|A. nigrum
Arum orientale Arum Lily ქალაკოდა.JPG|A. orientale
PikiWiki Israel 3833 arum palestinum.jpg|A. palaestinum
Pflanze Mallorca 1.jpg|A. pictum
Arum purpureospathum 01.jpg|A. purpureospathum
=Flower=
Arum concinnatum 002.JPG|A. concinnatum
Kreta-Aronstab.JPG|A. creticum
Purkersdorf - Naturschutzgebiet 58 - Speichberg - Aronstab (Arum).jpg|A. cylindraceum
Arum dioscoridis kz02.jpg|A. dioscoridis
Arum hygrophilum kz5.jpg|A. hygrophilum
Arum idaeum.jpg|A. idaeum
Arum italicum subsp. italicum kz02.jpg|A. italicum
Arum korolkowii 38577706.jpg|A. korolkowii
Arum maculatum - Osredek pri Dobrovi.jpg|A. maculatum
Arum maculatum 0 700.jpg|A. maculatum
Arum nigrum (26634339981).jpg|A. nigrum
Arum carpaticum.jpg|A. orientale
Arum palaestinum.JPG|A. palaestinum
Gardenology.org-IMG 0821 hunt07mar.jpg|A. pictum
Arum purpureospathum 01 (flower).jpg|A. purpureospathum
Arum sintenisii flowering.jpg|A. sintenisii
=Fruit=
Кліщинець Бессера (Arum besserianum) P1040233.jpg|A. besserianum
Kreta-Aronstab2.jpg|A. creticum
Arum cylindraceum4.JPG|A. cylindraceum
Arum dioscoridis - Spotted arum 05.jpg|A. dioscoridis
Italiaanse aronskelk (Arum italicum). Locatie, Tuinreservaat Jonkervallei 01.JPG|A. italicum
Arum korolkowii 84201263.jpg|A. korolkowii
PR Skalecký háj 12.jpg|A. maculatum
Arisaema.jpg|A. orientale
20210806 Hortus Botanicus Leiden - Zwarte aronskelk.jpg|A. palaestinum
Arumpurpureospathum.jpg|A. purpureospathum
=Corm=
Arum cylindraceum sl23.jpg|A. cylindraceum
Arum italicum bulbus.jpg|A. italicum