Phalaenopsis sumatrana
   (Korth. & Rchb.f 1860)
 
The Sumatran Phalaenopsis
Distribution : Sumatra (province of Palembang), Myanmar, Java, Bornéo
Thaïlande, Vietnam, Malaisie, Philippines
Synonyms

Phalaenopsis zebrina (Teijs & Binn 1863)

Phalaenopsis acutifolia (Lind 1886)

Polychilos sumatrana (Shim 1982)
 
    Epiphytic plant, exceptionally lithophyte, with stem very short, completely enclosed by imbricating leaf-sheaths.
    Roots many, flexuous, glabrous.
    Leaves arcuate or pendent, fleshy, obovate or obovate-oblong or oblong-elliptic, a little acute, canaliculate, of an intense green, long from 15 to 30 cm, broad from 4 to 11 cm.
    Flower stalk arcuate or erect, robust, green, as long as the foliage or shorter, carrying 2 to 6 flowers or sometimes more, seldom branching.
     Bracts small, fleshy, triangular, green, dorsally ducted.
     Flower from 5 to 6 cm, with very spread out segments. Sepals and petals similar and almost equal (petals somewhat smaller), largely oblong-
 

lanceolate to elliptic-lanceolate, acute, fleshy, somewhat shining.
    Sepals are dorsally carinate towards the apex, the petals a little narrower and wedge-shaped.
    Lip shorter than the sepals, spread out, very briefly onguiculate, deeply 3-lobed. Lateral lobes fleshy, erect and connivent, ligulate, apex truncated and bidentate, with external face provided of an acute and oblique hull and internal face with a well marked callus. Midlobe very thick and fleshy, almost semi-cylindrical, oblong, with higher face provided with a very thick and extremely prominent keel, densely hairy in its higher half, interior face a little concave with a median furrow. Between the lateral lobes, the disc is provided with an appendix fleshy, multifide, and, front, of another appendix a little longer and bifide.
    Semi-cylindrical column, edge of the clinandre largely winged , finely denticulate and fringed. Anther surmounted of a broad and fleshy circular wing.
    Pedicellate ovary of 4 cm long.

Column Phal.sumatrana (Sweet)
  
Lip Phal.sumatrana (Sweet)
 
 
Observations
 
    Very variable color. Floral segments white/cream tinted of green, barred transversely of red/brown. Lateral lobes of lip white with a large orange macula in the middle at level of the callus. White midlobe with some longitudinal mauve strippes even almost completely coloured.
     Flowering throughout the year, with a peak in spring.
     The flower is very scented and releases a strong odor of elder tree, especially in the morning. The plant often produces several floral stalks.
     Grow in warm forests, wet, on the trunks rather than on the branches, above the wet draughts or the rivers, in partnership with Phalaenopsis violacea.
     The flowering of Phalaenopsis sumatrana is one exceptional duration. Fecundation, in nature, of this plant appears to be a rare event, which would explain the longevity of the flowers awaiting the agent pollenisator a long time.
 
History

    Discovered by Gerssen, collector for Teijsmann in 1859 with Phalaenopsis violacea. Only one specimen survived, which flowers in 1860 in the botanical garden of Leyde under the name of Phalaenopsis zebrina. Introduced in England in 1864 by Low & Co company.
   The first illustration published by Korthals, Dutch botanist (1807-1892), before 1839 (undoubtedly 1833) described in fact a Phalaenopsis inscriptiosinensis and not the species currently known under the name of Phalaenopsis sumatrana.

 
Botanical varieties
    Phalaenopsis sumatrana var.alba (Wilson 1915)
    White flower, lip delicately stripped with wine colour on each side of the midlobe. Lateral lobes clear yellow.
 
    Phalaenopsis sumatrana var.paucivittata (Rchb.f 1882)
     Synonym. Phalaenopsis paucivittata (Fowl.1985).
     Segments of a milky white, provided of few bars brown/red. Two mauve stippes on each side of the midlobe. Very rare in nature. This Phalaenopsis is sometimes known in the Philippines islands under the name of Phalaenopsis bartonii.
 
Some photos of Phalaenopsis sumatrana
 
Average temperature relative humidity and pluviometry, evolution in Malaysia, area of Mersing
 

 
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