Musa lawitiensis Nasution & Supard. var. suratii (Argent) Häkkinen 2006

Häkkinen, Markku, 2006, Musa lawitiensis Nasution & Supard. (Musaceae) and its intraspecific taxa in Borneo, Adansonia (3) 28 (1), pp. 55-65 : 58-61

1. Musa lawitiensis Nasution & Supard. var. lawitiensis ( Fig. 3A )

Musa lawitiensis Nasution & Supard. , Bulletin Kebun

Raya Indonesia 8 (4): 128, fig. 1A-K (1998).

TYPE. — Indonesia. West Kalimantan, Bentuan Karimun National Park , I.1997, Supardiyono JN-TNBK 11 (holo-, BO; iso-, BO).

LIVING SPECIMEN EXAMINED AND DESCRIBED HERE. — Indonesia. West Kalimantan, Bentuan Karimun National Park, river Sibau , 243 m alt., 00°26.182’N, 112°32.389’E, 4.XI.2002 .

DESCRIPTION

Plant slender, suckering freely, close to parent plant, up to 4 suckers, position vertical.Mature pseudostem up to 3.1 m high, sheaths red-purple, underlying colour light green with purple blotches, shiny, sap watery. Petiole up to 14 cm long, petiole margins curved inward, petiole bases winged and clasping the pseudostem, margins curved inward with extensive brown-black blotches. Leaf habit drooping, lamina 125 cm long, 22 cm wide, narrowly elliptic, truncate at the apex, colour of upper surface green, lower surface medium green, appearance dull, heavily waxy on either surface, leaf bases asymmetric and both sides pointed, midrib dorsally green, ventrally yellow, with very corrugated lamina. Inflorescence hanging vertically downwards, peduncle 9 cm long, 3.5 cm in diameter, hairless and light green in colour, sterile bract 1 with small orange-red foliage lamina, deciduous at the opening of the first female flowers. Female bud, slender, 24 cm long, 4 cm wide, orange to red, pruinose with wax outside, imbricate, lifting several bracts at a time, not revolute before falling. Basal flowers hermaphrodite 8 cm long, the ovary yellowish, arrangement of ovules in two rows per loculus, the compound tepal 2.5 cm long, with two prominent thickened keels hyaline margins, green in colour, the lobes dark green, free tepal 2.3 cm long, boat-shaped, 5 cm long, translucent white, stamens 5 with fertile pollen, the style 2.7 cm long, cream stigma 0.3 cm in diameter. Male bud, lanceolate, 11 cm long, 3.5 cm wide, orange-red in colour, pruinose with wax outside, imbricate with obtuse purplish apex, lifting one bract at a time, not revolute before falling. Male flowers on average 6-8 per bract in 2 rows, falling with the bract, compound tepal 3.5 cm long, light yellow, ribbed at the dorsal angles, with 3-toothed green-yellow apex, the central lobe smaller than the outer lobes, free tepal 2.5 cm long, translucent white, oval, smooth, with triangular apex, stamens 5, filaments white, anthers yellow, anthers and style exserted, stigma orange, ovary straight, yellow, without pigmentation. Fruit bunch lax, with 8 hands and 5-8 fruits per hand on average, in 1-2 rows, fingers slightly curved towards to the stalk, individual fruit 8 cm long, slightly curved, rounded, pedicel 9 mm long, fruit apex bottle-necked shaped, without any floral relict, immature peel colour pale yellow becoming yellow at maturity, immature fruit pulp white, becoming white and soft at maturity.Seeds nearly rounded, tuberculate, about 1.5 mm in diameter, 60-70 seeds per fruit.

DISTRIBUTION

Musa lawitiensis var. lawitiensis abundantly grows on river banks in the Bentuan Karimun National Park at altitudes of over 200 m.

VERNACULAR NAMES

Pisang hutan, Pisang junai.

2. Musa lawitiensis Nasution & Supard. var. suratii (Argent) Häkkinen , stat. nov. ( Fig. 3B )

Musa suratii Argent , Garden’s Bulletin Singapore 52:

77, fig. 1A-P (2000).

TYPE. — Malaysia. Sabah, Kallang, Tenom District , 8.IX.1989, Surat & Lamb 268/89 (holo-, SAN; iso-, E).

LIVING SPECIMEN EXAMINED AND DESCRIBED HERE. — Malaysia. Sabah, Tenom district , 773 m alt., 04°28.838’N, 114°51.781’E, 19.X.2002 .

ADDITIONAL LIVING SPECIMENS EXAMINED. — Malaysia. Sarawak, Kapit division, 137 m alt., 01°38.949’N, 113°07.866’E, 4. V.2004. — Same data, 138 m alt., 01°48.176’N, 113°06.116’E, 4. V.2004. — Same data, 68 m alt., 01°56.242’N, 113°00.5786’E, 5. V.2004.

DESCRIPTION

Plant slender, suckering freely, close to parent plant, up to 7 suckers, position vertical.Mature pseudostem up to 3.5 m high, sheaths dark purplish black, underlying colour yellowish with purple blotches, shiny, sap watery. Petiole up to 11 cm long, petiole margins curved inward, petiole bases winged and clasping the pseudostem with slightly corrugated auricles with purple blotches. Leaf habit drooping, lamina 140 cm long, 20 cm wide, narrowly elliptic, truncate at the apex, colour of upper surface light green, lower surface watery-green, appearance dull, heavily waxy on either surface, leaf bases asymmet- ric and both sides pointed, midrib dorsally orange in colour, ventrally yellow, with very corrugated lamina.Inflorescence hanging vertically downwards, peduncle 14 cm long, 3.5 cm in diameter, slightly waxy, hairless and purple-brown in colour, sterile bract 1 with small orange to pink foliage lamina, deciduous at the opening of the first female flowers. Female bud, slender, 26 cm long, 4 cm wide, orange to pink, pruinose with wax outside, imbricate, lifting several bracts at a time, not revolute before falling. Basal flowers hermaphrodite 9 cm cm long, the ovary cream, arrangement of ovules in two rows per loculus, the compound tepal 2.7 cm long, with two prominent thickened keels hyaline margins, lower part paler green upper green in colour, free tepal 2.3 cm long, boat shaped, 5 cm long, translucent white, stamens 5 with fertile pollen, the style 2.7 cm long, cream stigma 0.3 cm in diameter. Male bud, slender with sharp apex, 14 cm long, 2.2 cm wide, orange-pink in colour, pruinose with wax outside, imbricate with sharp green apex, lifting one bract at a time, not revolute before falling. Male flowers on average 4-6 per bract in 1 row, falling with the bract, compound tepal 2.8 cm long, yellowish, ribbed at the dorsal angles, with 3-toothed greenish apex, the central lobe smaller than the outer lobes, free tepal 2.5 cm long, translucent white, three-pointed the lateral points broad, the central point smaller, firmer with greenish yellow apex, stamens 5, filaments white, anthers creamy white, anthers and style at the same level, stigma cream, ovary straight, yellow, without pigmentation. Fruit bunch lax, with 10 hands and 5-8 fruits per hand on average, in 2 rows, fingers curved upwards towards to the stalk, individual fruit 10 cm long, slightly curved, rounded, pedicel 6mm long, fruit apex bottle-necked shaped remaining light green at maturity, without any floral relict, immature peel colour pale green becoming yellow at maturity, immature fruit pulp white, becoming soft and creamy at maturity. Seeds tiny, ovoid, without any tubercles, about 1 mm in diameter, 90-100 seeds per fruit.

DISTRIBUTION

This population was along the logging road consisting only eight separate plants and was the only one known location in Sabah.

B C

A

F

D E

G H

I

FIG. 4. — Musa lawitiensis Nasution & Supard. var. kapitensis Häkkinen : A, hermaphrodite flower with ovary; B, compound tepal of hermaphrodite flower; C, style with stigma; D, staminode with anther; E, free tepal of hermaphrodite flower; F, compound tepal of male flower; G, stamens with pistil; H, free tepal of male flower; I, cross-section of petiole. M. Häkkinen et al. 997. Scale bar: 3 cm.

Figures

FIG. 3. — A, Musa lawitiensis Nasution & Supard. var. lawitiensis, male bud; B, Musa lawitiensis var. suratii (Argent) Häkkinen, male bud; C, Musa lawitiensis var. kapitensis Häkkinen, inflorescence; D, Musa lawitiensis var. sarawakensis Häkkinen, female bud with female basal flowers.