Areca tunku

Areca (ah-REHK-ah) tunku (TOON-koo)
Help to make this reference box better by uploading a representative photo of this palm.
Scientific Classification
Genus: Areca (ah-REHK-ah) Species: tunku (TOON-koo)
Synonyms
Areca bifaria (1997)
Native Continent
Asia
Morphology
Habit: Solitary Leaf type: Pinnate
Culture
Survivability index
Common names
None.

Habitat and Distribution

Thailand, Sumatra (Sumatera Utara), and Peninsular Malaysia. [[]]

Description

Solitary, unarmed, monoecious palm to 2.5 m tall. Stem often stilt-rooted at the base, dull green when young, becoming pale brown, 2-6 cm in diam., internodes 2- 3 cm, nodal scars about 0.5 cm wide. Crown composed of about 8 leaves, these sometimes tardily abscissing the whole crown tending io trap leaf litter. Crownshaft to 13-25 cm long, 3-7 cm in diam., often partially obscured by the marcescent leaf sheaths. Leaf variably dissected leaf sheaths l3- 20 cm long, dull green to brown, often tinged purple, drying pale brown, striate, bearing thin pale brown scalesi petiole absent to very short, not exceeding 5 cm long; rachis to 1 m long, adaxially channeled near the base, abaxially rounded or angled, pale brownish green, sometimes tinged purple; blade irregularly dissected, leaflets adaxially dark shiny green, slightly paler abaxially, usually borne close together, 5-24 on each side of the rachis, varying from narrow to broad, 22-65 x 0.7-10 cm, composed of l-6 folds, a cuminate and somewhat sigmoid except for the terminal shallowly lobed pair, main veins bearing minute brown punctiform scales. Inflorescence sometimes bursting through marcescenst heath. erect, 8.5: 22 cm, almost always branching to 1 order only, very rarely the basal most branch bearing a branch of the second order, all axes cream-colored, turning yellowish orange, greenish or deep purple; prophyll 8-22 x 2.5-4 cm, ancipitous, elliptic lanceolate, winged throughout, creamy brown to pale green, tinged with carmine purple, becoming striate on dryng, bearing bands of scattered pale brown scales peduncle 20-30 x 7-10 x 5 mm glabrous, bearing an inconspicuous, incomplete, low ridge like peduncular bract about 1 mm high, just above the prophyll scar; rachis to 7 cm long; rachillae 6-12, very stiff and stout. borne in two neat rows on either side of the rachis, congested at first, later often widely spreading, 5- 12 x 0.2- 0.4 cm, sometimes slightly curved, bearing flowers only along one side (the distal side); triads borne only at the very base of the rachillae, l-6 per rachilla, rarely absent, distally the rachillae bearing paired or solitary staminate flowers of the flowers, cream colored or greenish tinged, often markedly contrasting with the purplish rachillae. Staminate flowers terete, about 4-10 x 1.5-2 mm; calyx cup-shaped, sometimes strongly explanate, to 0.75 mm high, three-lobed, the lobes triangular to 1 x 1 mm; petals 3, distinct, 4.5-10 x L.5-2.5, abaxially slightly striate; stamens 6, filaments 0.75- 1.5 mm, anthers 2.5-5.5 x 1 mm, apically and basally sagittate; pollen monosulcate with finely punctate tectate exine; pistillode minute. Pistillate flowers at anthesis cream-colored, borne on enlarged rachillae; buds varying greatly in size depending on stage of development, just before anthesis to 19 x 9 mm; sepals 3, strongly imbricate, irregularly ovate l0 x 9 mm; petals 3, basally strongly imbricate l0 x 9 mm, with triangular valvate tips to 5 x 5 mm; staminodes 3, irregularly dentiform to strap-shaped; ovary ovoid 14 x 4 mm, stigmas 3 , strongly expressed in bud, expanding and becoming reflexed at anthesis, white, fleshy, triangular about 5 x 5 mm. Fruit borne on the enlarged, dark brown or blackened rachillae, up to about 12 fruits developing on a single inflorescence; mature fruit 3-4.5 x 1.5-3 cm, dull purplish green to brown, with blackened stigmatic remains borne on a white ringed beak to 12 x 6 mm; epicarp smooth, becoming striate on dryng; mesocarp thin, pale, inner fibers of mesocarp broad, black, conspicuous, closely adhering to the endocarp; endocarp thin, closely adhering to the seed. Seed to 25 x l5 mm; endosperm deeply ruminate, embryo basal. Seedling leaf bifid. (J. Dransfield & C. K. Lim, A new species of Areca from Peninsular Malaysia and Sumatra. 1992)/Palmweb. Editing by edric.

In Peninsular Malaysia Areca tunku is a palm of hill dipterocarp forest: in Sumatra it occurs in similar habitats. The North Sumatran population seems to consist of plants at the small end of the range of variation. Within populations in Terengganu, the range of variation is considerable, making suspect any separation of the Sumatran plants on the basis of size alone. The uniseriate staminate florrers suggest that Areca tunku is a member of Wendland and Drude's section Arecella in Furtado's sense (Furtado 1933). The swollen frequently purplish rachillae seem to suggest a relationship with Areca jugahpunya J. Dransf. and A. ahrnadii J. Dransf. (Dransfield 1984), two Bornean species. However, these two species are immediately distinguishable by their acaulescent habit; furthermore A. ahmadii has interfoliar inflorescences with very long peduncles and slender, less strongly beaked fruit, while A. jugahpunya is a much more massive palm, with a short peduncle as in A. tunku, but with much larger inflorescences with many (20) rachillae and large staminate flowers with petals connate for half their length. The peduncle form and colors of the inflorescence make A. tunku especially distinctive and striking. (J. Dransfield & C. K. Lim, A new species of Areca from Peninsular Malaysia and Sumatra. 1992)/Palmweb.