Dischidia

Dischidia
Dischidia collyris[1]
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Gentianales
Family: Apocynaceae
Subfamily: Asclepiadoideae
Genus: Dischidia
R.Br.

Dischidia is a genus of plants in the Milkweed family, Apocynaceae. They are epiphytes native to tropical areas of China, India and most areas of Indo-China. Dischidia are closely aligned with the sister genus Hoya. Unlike Hoya, the genus Dischidia is poorly known and has not been studied as closely.

Most Dischidia grow in arboreal ant nests of different species and some have developed a symbiotic relationship where the plant has developed modified leaves to either provide housing or storage. Of these there are two types of modification to the leaves. Three species develop bullate leaves which are hollow root-filled structures. These are Dischidia complex Griff, Dischidia major (Vahl) Merr. and Dischidia vidalii Becc. Both produce normal leaves (cordate in shape) in addition to the bullate leaves. These bullate leaves are formed when the outer margins of a leaf stop growing while the center of the leaf continues to grow. As time progresses the leaf margins curl under to close the gap which creates a small hole.[2]


A number of species develop imbricate leaves which hold tightly to the growing surface. The underside of the leaf has a space which is filled with roots that the ants take advantage of. Examples of these species are Dischidia astephana, Dichidia imbricata and Dischidia platyphylla , but there are many more. Plants with this type of growth habit are sometimes called Shingle Plants, which are given this name because the leaves tend to overlap as the grow up or down the surface and give the appearance of shingles on a roof.[3]

A few of the species in widespread cultivation.

Species

Accepted species[4]
D. major illustration from Pflanzenleben by Anton Kerner von Marilaun, 1913
D. bengalensis, Göttingen
D. imbricata on Millettia pinnata at Foster Botanical Garden, Honolulu
D. nummularia habitus, Berlin
D. hirsuta at Boltz Conservatory, Madison, WI
  1. Dischidia aberrans Schltr.
  2. Dischidia acuminata Costantin
  3. Dischidia acutifolia Maingay
  4. Dischidia apoensis Elmer.
  5. Dischidia albida Griff.
  6. Dischidia albiflora Griff.
  7. Dischidia alternans Schltr.
  8. Dischidia amphorantha K.Schum. & Lauterb.
  9. Dischidia angustifolia Miq.
  10. Dischidia antennifera Becc.
  11. Dischidia asperifolia Schltr.
  12. Dischidia astephana Scort. ex King & Gamble
  13. Dischidia atropurpurea Schltr.
  14. Dischidia australis Tsiang & P. T. Li
  15. Dischidia balansae Costantin
  16. Dischidia bengalensis Colebr.
  17. Dischidia bisetulosa O.Schwartz
  18. Dischidia boholensis (Schltr.) Livsch.
  19. Dischidia calva Pearson
  20. Dischidia chinensis Champ. ex Benth.
  21. Dischidia cleistantha Livsh.
  22. Dischidia clemensiae Schltr.
  23. Dischidia cochleata Blume
  24. Dischidia collyris Wall.
  25. Dischidia cominsii Hook.
  26. Dischidia complex Griff.
  27. Dischidia cornuta Livsh.
  28. Dischidia crassifolia Zipp. ex Schltr.
  29. Dischidia crassula Schltr.
  30. Dischidia cyclophylla Schltr.
  31. Dischidia cylindrica W.W.Sm.
  32. Dischidia dasyphylla Schltr.
  33. Dischidia deschampsii King & Gamble
  34. Dischidia digitiformis Becc.
  35. Dischidia dohtii T.B.Tran & Livsh.
  36. Dischidia dolichantha Schltr.
  37. Dischidia dohtii Tran & Livsh.
  38. Dischidia elmeri Schltr.
  39. Dischidia ericiflora Becc.
  40. Dischidia formosana Maxim.
  41. Dischidia fruticulosa Ridley
  42. Dischidia galactantha K.Schum.
  43. Dischidia gibbifera Schltr.
  44. Dischidia griffithii Hook.f.
  45. Dischidia hahliana Volkens
  46. Dischidia hellwigii Warb.
  47. Dischidia hirsuta Decne.
  48. Dischidia hollrungii Warb. ex K.Schum. & Lauterb.
  49. Dischidia hoyella Omlor
  50. Dischidia imbricata (Blume) Decne.
  51. Dischidia immortalis Guillaumin
  52. Dischidia indragirensis Schltr.
  53. Dischidia insularis Schltr.
  54. Dischidia khasiana Hook.f.
  55. Dischidia lanceolata (Blume) Decne.
  56. Dischidia lancifolia Ridley
  57. Dischidia latifolia (Blume) Decne.
  58. Dischidia lauterbachii K.Schum.
  59. Dischidia listerophora Schltr.
  60. Dischidia longepedunculata Ridl.
  61. Dischidia longiflora Becc.
  62. Dischidia longifolia Becc.
  63. Dischidia major (Vahl) Merr.
  64. Dischidia maxima Koord.
  65. Dischidia melanesica Fosberg
  66. Dischidia meleagridiflora O.Schwartz
  67. Dischidia merrillii Becc.
  68. Dischidia melanesica Fosberg
  69. Dischidia merrillii Schltr.
  70. Dischidia micholitzii N.E.Br.
  71. Dischidia micrantha Becc.
  72. Dischidia milnei Hemsl.
  73. Dischidia neurophylla Lauterb. & K.Schum.
  74. Dischidia nicobarica Didr.
  75. Dischidia nummularia R.Br.
  76. Dischidia obovata Decne.
  77. Dischidia oiantha Schltr.
  78. Dischidia ovata Benth.
  79. Dischidia oxyphylla Miq.
  80. Dischidia parvifolia Ridl.
  81. Dischidia pedunculata Warb.
  82. Dischidia peltata Blume
  83. Dischidia picta Blume
  84. Dischidia platyphylla Schlecther
  85. Dischidia polilloensis Kloppenb.
  86. Dischidia polyphylla Ridl.
  87. Dischidia pseudobenghalensis Costantin
  88. Dischidia puberula Decne.
  89. Dischidia pubescens Ridl.
  90. Dischidia punctata (Blume) Decne.
  91. Dischidia purpurea Merrill.
  92. Dischidia quinquangularis Schltr.
  93. Dischidia reniformis Schltr.
  94. Dischidia retusa Becc.
  95. Dischidia rhodantha Ridl.
  96. Dischidia rimicola Kerr
  97. Dischidia rosea Schl.
  98. Dischidia roseoflavida Schltr.
  99. Dischidia rumphii Miq.
  100. Dischidia ruscifolia Decne. ex Becc.
  101. Dischidia saccata Warb.
  102. Dischidia sagittata Decne.
  103. Dischidia sarasinorum Warb.
  104. Dischidia scortechinii King & Gamble
  105. Dischidia singaporensis Ridl.
  106. Dischidia singularis Craib
  107. Dischidia soronensis Becc.
  108. Dischidia spironema Turcz.
  109. Dischidia squamulosa Becc.
  110. Dischidia striata Schltr.
  111. Dischidia subulata Warb.
  112. Dischidia superba Rintz
  113. Dischidia tjidadapensis Bakh.f.
  114. Dischidia tomentella Ridl.
  115. Dischidia tonkinensis Costantin
  116. Dischidia tonsa Schltr.
  117. Dischidia torricellensis (Schltr.) P.I.Forst.
  118. Dischidia tricholoba Kerr
  119. Dischidia trichostemma Schltr.
  120. Dischidia truncata Decne.
  121. Dischidia vadosa Rintz
  122. Dischidia vidalii Becc.
Species moved to other genera[4]
  1. Dischidia chinghungensis, syn of Hoya chinghungensis
  2. Dischidia papuana, syn of Dischidiopsis papuana
  3. Dischidia yunnanensis, syn of Biondia yunnanensis

References

  1. ↑ illustration circa 1880 from Francisco Manuel Blanco (O.S.A.) - Flora de Filipinas
  2. ↑ S. Liede-Schumann (2006). The Genera of Asclepiadoideae, Secamonoideae and Periplocoideae (Apocynaceae): Descriptions, Illustrations, Identification, and Information Retrieval Version: 21 September 2000.
  3. ↑ Rintz, R.E. (1980). The Peninsular Malayan species of Dischidia (Asclepiadaceae). Blumea 26:81-126.
  4. ↑ 4.0 4.1 The Plant List, genus Dischidia