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Dimorphorchis

From Wikipedia, the free encyclopedia

Dimorphorchis
Dimorphorchis rossii
Botanical illustration of Dimorphorchis lowii
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Epidendroideae
Tribe: Vandeae
Subtribe: Aeridinae
Genus: Dimorphorchis
Rolfe
Type species
Dimorphorchis lowii (Benth. & Hook. f.) Rolfe[1]
Synonyms[2]
  • Arachnopapua R.Rice
  • Lowianthus Becc.

Dimorphorchis is a genus of flowering plants from the orchid family, Orchidaceae. It contains 9 species, which are native to Papua New Guinea, the Philippines, Indonesia, Malaysia, Solomon Islands, and Brunei.[2] It is remarkable for its two flower morphs present on the same plant.[3]

Description

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D. rossii distal flower. At Sakuya Konohana Kan.

Vegetative characteristics

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Its species are epiphytic, monopodial herbs with large, pendulous,[4] spreading, or erect[5] up to 200 cm long stems.[6] The basal part of the stem bears roots.[5] The distichously arranged,[5][4] coriaceous,[4] linear[5] up to 70 cm long leaves[6] have an unequally bilobed to acute apex.[5]

Generative characteristics

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The long,[7] glabrous[5] or pubescent,[5][7] pendent or erect, racemose or paniculate,[5] up to 3 metres long inflorescences[6] bear dimorphic (heteranthous)[3][6] or not dimorphic,[5] bisexual flowers.[6][8] The 2-3 flowers closest to the base of the inflorescence are strongly fragrant, slightly smaller, and of a different colour compared to the rest of the flowers, which are unscented and have wavy petals.[6] The four pollinia with an elliptic viscidium are grouped in two pairs.[5] It is unknown how the genus is pollinated.[5][6]

Taxonomy

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It was published by Robert Allen Rolfe in 1919[3][9] with Dimorphorchis lowii (Benth. & Hook. f.) Rolfe as the type species.[1]

Species

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It has nine species:[2]

Phylogenetic relationships

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Within the subtribe Aeridinae, it is the sistergroup to Thrixspermum.[7]

Etymology

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The generic name Dimorphorchis references the characteristic two flower morphs preset within the same plant.[3]

Ecology

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Habitat

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It can grow as a lithophyte or epiphyte in rainforests.[10]

References

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  1. ^ a b Missouri Botanical Garden. (n.d.-d). Dimorphorchis Rolfe. Tropicos. Retrieved December 2, 2024, from http://legacy.tropicos.org/Name/40031513
  2. ^ a b c "Dimorphorchis Rolfe". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 8 February 2023.
  3. ^ a b c d The Orchid review (Vol. 27, Issues 321–322, p. 149). (1893). Orchid Review ltd.]. https://www.biodiversitylibrary.org/page/37102243
  4. ^ a b c Teoh, E. S., & Teoh, E. S. (2021). Dimorphorchis Rolfe. Orchid Species from Himalaya and Southeast Asia Vol. 1 (A-E), 465-470.
  5. ^ a b c d e f g h i j k Pridgeon, A. M., Cribb, P. J., Chase, M. W., & Rasmussen, F. N. (2014). Genera Orchidacearum volume 6: Epidendroideae (Part 3). pp. 172–175. OUP Oxford.
  6. ^ a b c d e f g Wood, Jeffrey (2005). "518. Dimorphorchis rossii var. graciliscapa: Orchidaceae". Curtis's Botanical Magazine. 22 (1): 42–46. ISSN 1355-4905.
  7. ^ a b c Zou, L. H., Huang, J. X., Zhang, G. Q., Liu, Z. J., & Zhuang, X. Y. (2015). A molecular phylogeny of Aeridinae (Orchidaceae: Epidendroideae) inferred from multiple nuclear and chloroplast regions. Molecular phylogenetics and evolution, 85, 247-254.
  8. ^ Hutton, R. (2011). Dimorphorchis – Borneo beauties. The New Zealand Internet Orchid Review, 16, 26. http://www.orchidcouncil.org.nz/wp-content/uploads/2023/03/Issue-16-final.pdf
  9. ^ Dimorphorchis Rolfe. (n.d.). International Plant Names Index. Retrieved December 2, 2024, from https://www.ipni.org/n/29278-1
  10. ^ Ormerod, P. (2013). A new, orange-flowered Dimorphorchis from Maluku, Indonesia. Malesian Orchid Journal, 12, 33-37.
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