Nageia

Nageia is a genus of conifers belonging to the podocarp family Podocarpaceae.[4] Nageia includes evergreen shrubs and trees, from one to 54 meters in height. A 2009 treatment of the genus recognized five species.[5] Some authors consider Nageia formosensis to be a separate species from Nageia nagi, thus recognizing six species. The podocarp genera have been reshuffled by various botanists. Most recently, several species formerly classed as Nageia were moved to the new genus Retrophyllum, while Nageia falcata and Nageia mannii were moved to the new genus Afrocarpus.

Nageia
Nageia nagi[1]
Scientific classification
Kingdom: Plantae
Clade: Tracheophytes
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Podocarpaceae
Genus: Nageia
Gaertn. 1788 not Roxb. 1832 (syn of Putranjiva in Putranjivaceae)[2]
Type species
Nageia nagi
Synonyms[3]

Decussocarpus de Laub.

Description

Nageia are evergreen woody plants that usually grow as trees but may also rarely be shrubs, varying in height from one to 54 meters.[6] The branching is irregular.[7] The thin and hard bark often peels with scale-like plates.[7]

The leaves are simple and flat. The phyllotaxis or leaf arrangement can be spiral or subopposite and nearly decussate.[7][8] The leaf petioles are frequently twisted so the leaves form a flat plane around the shoot.[6][7] The leaf blade is elliptic, ovate-elliptic or lanceolate in shape.[6][7] Juvenile leaves are similar in shape to the adult leaves but may be larger or smaller depending on the species.[8] The leaves have multiple parallel longitudinal veins converging toward the ends. Stomata may be found on either both surfaces of the leaf or only the abaxial or underside. The leaf surface is coriaceous.[7]

Nageia are generally dioecious, with male pollen cones and female seed cones borne on separate individual plants but may sometimes be monoecious. The cones are pedunculate and develop from axillary buds.[7][8]

The pollen cones are long and ovoid-cylindric in shape. They may be solitary or grow in small spicate groups of two to six cones.[7][8] Each pollen cone has numerous spirally inserted microsporophylls. The microsprophylls may be triangular or apiculate in shape. Each of them has two basal pollen sacs with bisaccate pollen.[7]

The seed cones are solitary and have long peduncles. They have several sterile and one or rarely two fertile scales, each fertile scale with one seed producing ovule.[7] Depending on the species, as the cone matures, the sterile scales may fuse and become fleshy as in the closely related Podocarpus or they may wither.[7][8] A part of the cone scale supporting the ovule develops into a drupe-like fleshy covering known as the epimatium.[6][7] The fleshy parts of the cones attract birds, which then disperse the seeds in their droppings.[9]

The species of Nageia are distinguished from similar Podocarpus and the other genera in the Podocarpaceae by their broad, flat subopposite leaves with no midrib, superficially similar to those of the unrelated Agathis (Araucariaceae). Nageia is the only genus in Podocarpaceae with multi-veined leaves.

Distribution

Nageia can be found in the tropical and subtropical moist broadleaf forests of Asia and Australasia, from Assam in eastern India across Southeast Asia to southern China and southern Japan, and across Malesia, from the Malay peninsula across Indonesia to New Guinea and New Britain.[3] An outpost of N. wallichiana is found in the South Western Ghats montane rain forests of southern India, where it is thought to be a relatively recent colonist in biogeographical terms.

Nageia, like many podocarps, can usually be found scattered throughout the forest mixed with other trees, and is rarely if ever found growing in pure stands. The wood is yellowish, typical of podocarps, and a few species are locally important for lumber.

Classification

The genus contains six species:[3][7]

ImageScientific nameDistribution
Nageia fleuryiS China, E Indochina
Nageia formosensisTaiwan
Nageia maximaSarawak
Nageia motleyiS Thailand, W Malaysia, Borneo, Sumatra
Nageia nagiS China (incl. Hainan), Kyushu in Japan, Taiwan
Nageia wallichianaSW India; widespread from Assam + Yunnan to Maluku


formerly included[3]

moved to other genera: Acmopyle Afrocarpus Amentotaxus Cephalotaxus Dacrycarpus Dacrydium Falcatifolium Madhuca Parasitaxus Podocarpus Prumnopitys Putranjiva (Putranjivaceae) Retrophyllum Sundacarpus

  1. N. acutifolia — Podocarpus acutifolius
  2. N. affinis — Podocarpus affinis
  3. N. alpina — Podocarpus lawrencei
  4. N. amara — Sundacarpus amarus
  5. N. andina — Prumnopitys andina
  6. N. angustifolia — Podocarpus parlatorei
  7. N. appressa — Podocarpus macrophyllus var. maki
  8. N. argotaenia — Amentotaxus argotaenia
  9. N. aristulata — Podocarpus angustifolius
  10. N. beccarii — Dacrydium beccarii
  11. N. bracteata — Podocarpus bracteatus
  12. N. chilina — Podocarpus salignus
  13. N. chinensis — Podocarpus macrophyllus var. maki
  14. N. comptonii — Retrophyllum comptonii
  15. N. coriacea — Podocarpus coriaceus
  16. N. corrugata — Podocarpus macrophyllus var. maki
  17. N. costalis — Podocarpus costalis
  18. N. cumingii — Dacrycarpus cumingii
  19. N. cupressina — Dacrycarpus imbricatus
  20. N. curvifolia — Prumnopitys montana
  21. N. dacrydioides — Dacrycarpus dacrydioides
  22. N. discolor — Podocarpus neriifolius
  23. N. drouyniana — Podocarpus drouynianus
  24. N. elata — Podocarpus elatus
  25. N. elongata — Podocarpus elongatus
  26. N. endlicheriana — Podocarpus neriifolius
  27. N. ensifolia — Podocarpus spinulosus
  28. N. eurhyncha — Sundacarpus amarus
  29. N. excelsa — Dacrycarpus dacrydioides
  30. N. falcata — Afrocarpus falcatus
  31. N. falciformis — Falcatifolium falciforme
  32. N. ferruginea — Prumnopitys ferruginea
  33. N. flagelliformis — Podocarpus macrophyllus var. maki
  34. N. glomerata — Podocarpus glomeratus
  35. N. gnidioides — Podocarpus gnidioides
  36. N. hallii — Podocarpus cunninghamii
  37. N. insignis — Amentotaxus argotaenia
  38. N. japonica (Siebold ex Endl.) Kuntze 1891 not Gaertn. 1788 - Podocarpus macrophyllus var. maki
  39. N. kirkiana — Podocarpus acutifolius
  40. N. koraiana — Cephalotaxus harringtonii
  41. N. laeta — Podocarpus spinulosus
  42. N. lambertii — Podocarpus lambertii
  43. N. latifolia (Thunb.) Kuntze 1891 not Gordon 1858 - Podocarpus latifolius
  44. N. leptostachya — Podocarpus neriifolius
  45. N. macrophylla — Podocarpus macrophyllus
  46. N. macrostachya — Podocarpus oleifolius
  47. N. madagascariensis — Podocarpus madagascariensis
  48. N. mannii — Afrocarpus mannii
  49. N. mannii var. dawei — Afrocarpus dawei
  50. N. mannii var. usambarensis — Afrocarpus usambarensis
  51. N. meyeriana — Afrocarpus falcatus
  52. N. minor — Retrophyllum minus
  53. N. montana — Prumnopitys montana
  54. N. neglecta — Podocarpus neriifolius
  55. N. neriifolia — Podocarpus neriifolius
  56. N. nivalis — Podocarpus nivalis
  57. N. novae-caledoniae — Podocarpus novae-caledoniae
  58. N. nubigena — Podocarpus nubigenus
  59. N. oleifolia — Podocarpus oleifolius
  60. N. palembanica — Madhuca palembanica
  61. N. pancheri — Acmopyle pancheri
  62. N. parvifolia — Podocarpus lawrencei
  63. N. piresii — Retrophyllum piresii
  64. N. polystachya — Podocarpus polystachyus
  65. N. purdieana — Podocarpus purdieanus
  66. N. putranjiva — Putranjiva roxburghii
  67. N. rospigliosii — Retrophyllum rospigliosii
  68. N. rumphii — Podocarpus rumphii
  69. N. salicifolia — Podocarpus salicifolius
  70. N. sellowii — Podocarpus sellowii
  71. N. spicata — Prumnopitys taxifolia
  72. N. spinulosa — Podocarpus spinulosus
  73. N. sprucei — Podocarpus sprucei
  74. N. taxoides — Falcatifolium taxoides
  75. N. tenuifolia — Dacrycarpus vieillardii
  76. N. teysmannii — Podocarpus teysmannii
  77. N. thevetiifolia — Podocarpus polystachyus
  78. N. thunbergii — Podocarpus latifolius
  79. N. totara — Podocarpus totara
  80. N. usta — Parasitaxus ustus
  81. N. valdiviana — Prumnopitys andina
  82. N. vieillardii — Dacrycarpus vieillardii
  83. N. vitiensis — Retrophyllum vitiense

References

  1. illustration from Flora Japonica, Sectio Prima (Tafelband). 1870 by Philipp Franz von Siebold and Joseph Gerhard Zuccarini
  2. Kew World Checklist of Selected Plant Families, Nageia Roxb.
  3. Kew World Checklist of Selected Plant Famiiles, Nageia Gaertn.
  4. Christopher N. Page. 1990. "Podocarpaceae" pages 332-346. In: Klaus Kubitzki (general editor); Karl U. Kramer and Peter S. Green (volume editors) The Families and Genera of Vascular Plants volume I. Springer-Verlag: Berlin;Heidelberg, Germany. ISBN 978-0-387-51794-0
  5. James E. Eckenwalder. 2009. Conifers of the World. Timber Press: Portland, OR, USA. ISBN 978-0-88192-974-4.
  6. Earle, Christopher J. (2012). "Nageia". The Gymnosperm Database, conifers.org. Retrieved April 2, 2016.
  7. Farjon, Aljos (2010). A Handbook of the World's Conifers. Leiden: Brill. p. 518. ISBN 9789004177185.
  8. "Nageia". eFloras: Flora of China. Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA. 1999. Retrieved April 2, 2016.
  9. Flora of China Vol. 4 Page 79 竹柏属 zhu bai shu Nageia Gaertner, Fruct. Sem. Pl. 1: 191. 1788.
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