Epipogium aphyllum

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Epipogium aphyllum
Habitus
Detail of flower
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
Order: Asparagales
Family: Orchidaceae
Tribe: Gastrodieae
Subtribe: Epipogiinae
Genus: Epipogium
Species: E. aphyllum
Binomial name
Epipogium aphyllum
Sw.
Synonyms

Satyrium epipogium L.

Epipogium aphyllum, the ghost orchid (not to be confused with the American ghost orchid, Dendrophylax lindenii) is a hardy myco-heterotrophic orchid lacking chlorophyll.

It is famous for its unpredictable appearance; in many localities it has been seen just once.[1] It is found in beech, oak, pine and spruce forests on base-rich soils. It is a rare and critically endangered plant in habitat, and is believed to be extinct throughout much of its former range, although it has been recently confirmed in the United Kingdom, an area where the plants were believed to have gone extinct.

The plants are protected in many locales, and removing the plants from habitat or disturbing the plants can be a very serious matter in many jurisdictions, even for scientific study. These plants are exceptionally rare and should never be removed from habitat or disturbed.[2]

Biology

Once thought to be saprophytic, these hardy plants are actually obligate mycoheterotrophs (or epiparasites) that obtain nutrients from mycorrhizal networks involving basidomycete fungi that are in turn associated with the roots of various species of coniferous trees. They grow from an underground, burrowing stem which lacks chlorophyll and possesses ephemeral leaves that are small scales. The plants only emerge above ground to flower.

The plants have an extremely wide range of distribution, but are exceptionally rare in habitat. They have been reported from Japan, Russia, The United Kingdom, and France. The plants are all found in areas which typically experience cold winters. The plant's rhizomes are densely colonized by fungi bearing clamp-connections and dolipores, all basidiomycetes, gill or pore-forming mushroom species that are normally found growing in mycorrhizal association with the roots of coniferous trees.

These plants harness an array of fungal symbionts across several families, often simultaneously. Analysis of these plants have identified Inocybe species as exclusive symbionts for 75% of the plants in habitat, as well as others (Hebeloma, Xerocomus, Lactarius and Thelephora). The plants also host ascomycete endophytes, which appear to assist the plant in parasitizing some of the plant's basidiomycete symbionts.[2]

The plants defy cultivation outside of laboratory conditions, as they require not only specific fungal symbionts, but also specific host trees that these mushroom species form mycorrhizal relationships with. Large plants of this species can produce a rather stunning woodland display with up to a dozen flower stalks at once bearing 3–4 flowers each growing out of coniferous leaf litter.[1]

References

  1. ↑ 1.0 1.1 Juliette Jowit (March 8, 2010). "Ghost orchid comes back from extinction". The Guardian. 
  2. ↑ 2.0 2.1 Melanie Roy, Takahiro Yagame, Masahide Yamato, Koji Iwase, Christine Heinz, Antonella Faccio, Paola Bonfante & Marc-Andre Selosse (2009). "Ectomycorrhizal Inocybe species associate with the mycoheterotrophic orchid Epipogium aphyllum but not its asexual propagules". Annals of Botany 104 (3): 595–610. doi:10.1093/aob/mcn269. PMC 2720653. PMID 19155220. 

External links

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