Carrion flower

Summary

Carrion flowers, also known as corpse flowers or stinking flowers, are mimetic flowers that emit an odor that smells like rotting flesh. Apart from the scent, carrion flowers often display additional characteristics that contribute to the mimesis of a decaying corpse. These include their specific coloration (red, purple, brown), the presence of setae and orifice-like flower architecture. Carrion flowers attract mostly scavenging flies and beetles as pollinators. Some species may trap the insects temporarily to ensure the gathering and transfer of pollen.

Amorphophallus titanum in Wilhelma Botanical and Zoological Gardens, Stuttgart

Plants known as "carrion flower" edit

Amorphophallus edit

Many plants in the genus Amorphophallus (family Araceae) are known as carrion flowers. One such plant is the Titan arum (Amorphophallus titanum), which has the world's largest unbranched inflorescence. Rather than a single flower, the titan arum presents an inflorescence or compound flower composed of a spadix or stalk of small and anatomically reduced male and female flowers, surrounded by a spathe that resembles a single giant petal. This plant has a mechanism to heat up the spadix enhancing the emission of the strong odor of decaying meat to attract its pollinators, carrion-eating beetles and "flesh flies" (family Sarcophagidae). It was first described scientifically in 1878 in Sumatra.[1]

 
Flower of Rafflesia kerrii, in Khao Sok National Park, Southern Thailand.

Rafflesia edit

Flowers of plants in the genus Rafflesia (family Rafflesiaceae) emit an odor similar to that of decaying meat. This odor attracts the flies that pollinate the plant. The world's largest single bloom is R. arnoldii. This rare flower is found in the rainforests of Borneo and Sumatra. It can grow to be 90 centimetres (3 ft) across and weigh up to 7 kilograms (15 lb). R. arnoldii is a parasitic plant on Tetrastigma vine, which grows only in primary rainforests. It has no visible leaves, roots, or stem. It does not photosynthesize, but rather uses the host plant to obtain water and nutrients.

 
House fly landing on a flower of Orbea variegata.

Stapelia edit

Plants in the genus Stapelia are also called "carrion flowers". They are small, spineless, cactus-like succulent plants. Most species are native to South Africa, and are grown as potted plants elsewhere. The flowers of all species are hairy to varying degrees and generate the odor of rotten flesh. The color of the flowers also mimics rotting meat. This attracts scavenging flies, for pollination. The flowers in some species can be very large, notably Stapelia gigantea can reach 30 cm (12 in) in diameter.

Smilax or Nemexia edit

In North America, the herbaceous vines of the genus Smilax are known as carrion flowers. These plants have a cluster of small greenish flowers. The most familiar member of this groups is Smilax herbacea. These plants are sometimes placed in the genus Nemexia.

Bulbophyllum (Orchid) edit

Orchids of the genus Bulbophyllum produce strongly scented flowers. The flowers produce various odors resembling sap, urine, blood, dung, carrion, and, in some species, fragrant fruity aromas. Most are fly-pollinated, and attract hordes of flies. Bulbophyllum beccarii, Bulbophyllum fletcherianum and Bulbophyllum phalaenopsis in bloom have been likened to smelling like a herd of dead elephants. Their overpowering floral odors are sometimes described as making it difficult to walk into a greenhouse in which they in bloom.[2]

Scent edit

The sources of the flowers' unique scent are not fully identified, partly due to the extremely low concentration of the compounds (5 to 10 parts per billion). Biochemical tests on Amorphophallus species revealed foul-smelling dimethyl sulfides such as dimethyl disulfide and dimethyl trisulfide, and in other species, trace amounts of amines such as putrescine and cadaverine have been found.[3] Methyl thioacetate (which has a cheesy, garlic-like odor) and isovaleric acid (smells of sweat) also contribute to the smell of the flower. Trimethylamine is the cause of the "rotten fish smell" towards the end of the flower's life. [4]

Pollination edit

Both visual interactions and odor are important attractants for pollinators.[5] In order for pollination to occur, a relationship of attraction and reward must be present between the flower and the pollinator. The pollinator's body mechanically promotes pollen adherence, which is necessary for effective pollen dispersal. The recognizable scent of the carrion flowers is produced in the petals of both male and female flowers and the pollen reward attracts beetles and flies. [6] Popular pollinators of carrion flowers are blowflies (Calliphoridae), house flies (Muscidae), flesh flies (Sarcophagidae) and varying types of beetles, due to the scents produced by the plant.[7] Fly pollinators are typically attracted to pale, dull plants or those with translucent patches. Additionally, these plants produce pollen, do not have present nectar guides and flowers resemble a funnel or complex trap.[8] The host plant can sometimes trap the pollinator during the pollination/feeding process.

Other plants with carrion-scented flowers edit

Annonaceae

Apocynaceae

Araceae

Aristolochiaceae

Asparagaceae

Balanophoraceae

Bignoniaceae

Burmanniaceae

Cytinaceae

Iridaceae

Malvaceae

Melanthiaceae

Orchidaceae

See also edit

  • Stinkhorn — fungi that use the same basic principle for spore dispersal
  • Aseroe rubra — fungi that use the same basic principle for spore dispersal

References edit

  1. ^ Live Science
  2. ^ Illustrated Encyclopedia of Orchids ISBN 0-88192-267-6
  3. ^ Wilson, Elizabeth K. (2003-06-30). "A Fantastic Stink". Chemical & Engineering News. 81 (26): 27. doi:10.1021/cen-v081n005.p027. ISSN 0009-2347. Retrieved 2007-04-29.
  4. ^ "The Smelly Chemistry of the Titan Arum 'Corpse Flower'". Compound Interest. 2017-06-27. Retrieved 2022-05-03.
  5. ^ du Plessis, Marc; Johnson, Steven D.; Nicolson, Susan W.; Bruyns, Peter V.; Shuttleworth, Adam (2018-03-01). "Pollination of the "carrion flowers" of an African stapeliad (Ceropegia mixta: Apocynaceae): the importance of visual and scent traits for the attraction of flies". Plant Systematics and Evolution. 304 (3): 357–372. doi:10.1007/s00606-017-1481-0. ISSN 2199-6881. S2CID 3529359.
  6. ^ Sawyer, Neil W.; Anderson, Gregory J. (1998). "Reproductive Biology of the Carrion-Flower, Smilax Herbacea (Smilacaceae)". Rhodora. 100 (901): 1–24. ISSN 0035-4902. JSTOR 23313266.
  7. ^ Johnson, Steven (July 11, 2016). "Quick Guide: Carrion Flowers" (PDF). Current Biology. 26 (13): 543–576. doi:10.1016/j.cub.2015.07.047. PMID 27404246. S2CID 3924473.
  8. ^ "Fly Pollination". www.fs.usda.gov. Retrieved 2022-05-05.

External links edit

  • All about stinking flowers
  • Jürgens, Andreas; Shuttleworth, Adam (2015-08-06). Carrion Ecology, Evolution, and Their Applications. CRC Press. pp. 361–386. doi:10.1201/b18819-20. ISBN 9781466575462. Carrion and Dung Mimicry in Plants<ref>