Musa lawitiensis Nasution & Supard. var. kapitensis Häkkinen, 2006

Häkkinen, Markku, 2006, Musa lawitiensis Nasution & Supard. (Musaceae) and its intraspecific taxa in Borneo, Adansonia (3) 28 (1), pp. 55-65 : 61-63

3. Musa lawitiensis Nasution & Supard. var. kapitensis Häkkinen , var. nov.

( Figs 3C ; 4)

A specie typica permultis surculis, vaginis foliorum flavobrunneis, succo lacteo ac non aqueo, foemino alabastro extus valde ceraceo cum unica bractea simul erecta atque permultis quidem 10 fructibus per racemi manum praecipue differt.

TYPE. — Malaysia. Sarawak, Kapit divisision, 242 m alt., 01°50.960’N, 113°02.759’E, 4. V.2004, Häkkinen M. et al. 997 (holo-, SAR; iso-, HUMS).

DESCRIPTION

Plant slender, suckering freely, close to parent plant, clumping up to 20 suckers, position near vertical. Mature pseudostem up to 1.8 m high, sheaths yellow-brown, underlying colour yellow-green with purple blotches, dull, sap milky. Petiole up to 25 cm long, petiole margins curved inward, petiole bases winged and clasping the pseudostem with brownblack blotches. Leaf habit drooping, lamina 140 cm long, 22 cm wide, narrowly elliptic, truncate at the apex, colour of upper surface silvery, lower surface light green, appearance dull, heavily waxy on either surface, leaf bases asymmetric and both sides pointed, midrib dorsally light green, ventrally bright yellow, with very corrugated lamina. Inflorescence hanging vertically downwards, peduncle 13 cm long, 1.2 cm in diameter, hairless and medium-green in colour, sterile bract 1 with small orange-red foliage lamina with small leaf like green tip, deciduous at the opening of the first female flowers. Female bud, slender, 25 cm long, 4 cm wide, orange to red, heavily waxy outside, imbricate, lifting one bract at a time, not revolute before falling. Basal flowers hermaphrodite 8 cm long, the ovary pale yellow, arrangement of ovules in two rows per loculus, the compound tepal 3 cm long, with two prominent thickened keels hyaline margins, green in colour upper part, yellow in lower part, the 4 lobes dark green, free tepal 2.3 cm long, boat shaped, translucent white with green triangular tip, the style 3 cm long, cream stigma 0.3 cm in diameter. Male bud, lanceolate, 9 cm long, 3.3 cm wide, orange-red in colour, moderate waxy outside, imbricate with obtuse dark red apex, lifting one bract at time, not revolute before falling. Male flowers on average 5-8 per bract in 2 rows, falling usually after the bract, compound tepal 3.5 cm long, light yellow, ribbed at the dorsal angles, with 3-toothed green apex, the central lobe smaller than the outer lobes, free tepal 2.8 cm long, translucent white, oval, smooth, with green triangular apex, stamens 5, filaments cream, anthers cream, anthers and style at the same level, stigma light green, ovary arched, cream, without pigmentation. Fruit bunch lax, with 7 hands and 10-12 fruits per hand on average, in 2 rows, fingers curved slightly towards to the stalk, individual fruit 8.5 cm long, slightly curved, rounded, pedicel 8 mm long, fruit apex bottle-necked shaped, with floral relict, immature fruit peel colour pale yellow and becoming yellow at maturity, immature fruit pulp white, becoming soft and creamish at maturity. Seeds tiny, ovoid, with some tubercles, about 1.2 mm in diameter, 80-90 seeds per fruit.

DISTRIBUTION

Musa lawitiensis var. kapitensis abundantly grows on river banks of the river Mengiong in Sarawak’s side of the Mount Lawit.

4. Musa lawitiensis Nasution & Supard. var. sarawakensis Häkkinen , var. nov. ( Figs 3D ; 5 )

A specie typica vaginis foliorum viridulis, foemino alabastro laete flavo, basalibus floribus foemineis ac non hermaphroditis, masculinis floribus 5 per bracteam in unica serie dispositis, cum tepalo composito 5-dentato atque fructuum racemo ex tantum 4 manibus constante praecipue differt.

TYPE. — Malaysia. Sarawak, Kapit divisision, 712 m alt., 01°42.012’N, 113°05.451’E, 4. V.2004, Häkkinen M. et al. 997-1 (holo-, SAR; iso-, HUMS).

DESCRIPTION

Plant slender, suckering freely, close to parent plant, clumping up to 6 suckers, position near vertical. Mature pseudostem up to 2 m high, sheaths greenish, underlying colour light green with small purple blotches, dull, watery.Petiole up to 30 cm long, petiole margins overlapping, petiole bases winged and clasping the pseudostem with small black blotches. Leaf habit drooping, lamina 170 cm long, 23 cm wide, narrowly elliptic, truncate at the apex, colour of upper surface dark green, lower surface green, appearance dull, waxy on either surface, leaf bases asymmetric and both sides pointed, midrib dorsally light green, ventrally green-yellow, with very corrugated lamina. Inflorescence hanging vertically downwards, peduncle 30 cm long, 2 cm in diameter, hairless, waxy and silvery green in colour, sterile bract 1 with small bright yellow foliage lamina, deciduous at the opening of the first female flowers. Female bud, slender, 23 cm long, 4 cm wide, bright yellow, heavily waxy outside, imbricate, lifting several bracts at a time, not revolute before falling. Basal flowers female 6.5 cm long, the ovary greenish yellow, arrangement of ovules in two rows per loculus, the compound tepal 3.6 cm long, with two prominent thickened keels hyaline margins, green in colour upper part, pale yellow in lower part, the 3 lobes dark green, free tepal 2.7 cm long, boat shaped, white with green triangular tip, the style 3.4 cm long, whitish stigma 0.3 cm in diameter. Male bud, slender with sharp apex, 13 cm long, 2.5 cm wide, orange to yellow in colour, with wax outside, imbricate with obtuse dark red apex sharp green apex, lifting one bract at a time, not revolute before falling.Male flowers on average 5 per bract in 1 row, falling with the bract, compound tepal 3.7 cm long, cream in lower and green in upper part, ribbed at the dorsal angles, with 5-toothed green apex, the 3 central lobes are smaller than the outer lobes, free tepal 3 cm long, translucent white, oval, smooth, with green triangular apex, stamens 5, filaments cream, anthers brown, anthers and style inserted, stigma light green, ovary straight, cream, without pigmentation. Fruit bunch lax, with 4 hands and 8-10 fruits per hand on average, in 2 rows, fingers curved slightly towards to the stalk, individual fruit 8.5 cm long, slightly curved, rounded, pedicel 6 mm

B A

C

D

H E

F G

long, fruit apex bottle-necked shaped, without any floral relict, immature fruit peel colour light green and becoming yellow at maturity, immature fruit pulp white, becoming soft and creamish at maturity. Seeds tiny, ovoid, with some tubercles, about 1.2 mm in diameter, 85-90 seeds per fruit.

DISTRIBUTION

This population was along the logging road consisting of only 15 separate plants and was the only population that we could locate in the area.

ADDITIONAL UNIDENTIFIED SPECIMENS OF MUSA LAWITIENSIS VARIETIES  FIG. 2 

5. Malaysia. Sarawak, Sri Aman division, Lubok Andu, river Delok, Christensen 1066 (AAU, E, SAR).

6. Malaysia. Sarawak, Bintulu division, Long Murum, Leng Guan ( KEP) .

7. Malaysia. Sarawak, Miri division, Usum Apau, Ruth Kiew ( SING) .

8. Indonesia. East Kalimantan, West Kutai, 1600 m alt., M. Kato H. Wiriadinata B-6207 (KYO).

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.

FIG. 5. — Musa lawitiensis Nasution & Supard. var. sarawakensis Häkkinen: A, female flower with ovary; B, compound tepal of female flower; C, style with stigma; D, free tepal of female flower; E, compound tepal of male flower; F, stamens with pistil; G, free tepal of male flower; H, cross-section of petiole. M. Häkkinen et al. 997-1. Scale bar: 4 cm.

FIG. 2. — Distribution map of Musa lawitiensis Nasution & Supard. varieties: 1, 5-8, var. lawitiensis; 2, var. suratii (Argent) Häkkinen; 3, var. kapitensis Häkkinen; 4, var. sarawakensis Häkkinen. 1-4, author’s field observations; 5-7, author’s personal observation; 8, after Nasution & Supardiyono 1998.