Ravenea beentjei Rakotoarin. & J.Dransf., Kew Bull. 65(2): 298 (2010)

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Distribution

Map uses TDWG level 3 distributions (http://www.nhm.ac.uk/hosted_sites/tdwg/geogrphy.html)

Habitat

Discussion

Diagnosis

Conservation

Description

  • Medium-sized, solitary, dioecious palm. Trunk 3.5 - 10 m tall, 8- 15 cm diam., internodes 4- 11 cm, bark brown, wood soft, base of the crown bulbous, c. 11 cm across. Leaves 8- 15 in the crown, porrect to pendulous, arching, marcescent, occasionally trapping litter; sheath 50-90 x 10-15 cm, yellowish but covered with brown blackish indumentum, margins disintegrating and fibrous; petiole 30- 150 cm long, 3.5- 3.8 ?x 1.5-2 cm in cross section, slightly channelled, margins sharp, abaxial surface covered in caducous white to greyish tomentum; rachis 2 . 3.50 m long, 1.2- 2 ?x 2.2- 2.6 cm in cross section in mid-leaf, keeled, pale green, with irregular grey to brown tomentum, becoming glabrescent; leaflets stiff, regularly arranged, arranged in one plane, dark green, 46 . 55 on each side of the rachis, the proximal leaflets 52- 123 ?x 0.8- 2 cm, the median leaflets 116-124 ?x 4.8- 6 cm, the distal leaflets 21- 42 ?x 0.8- 2.9 cm, leaflets spaced 4-6 cm apart, abaxial surface with scattered brown scales and ramenta. Inflorescences interfoliar, solitary. Staminate inflorescence pendulous, branched to 2 orders, peduncle 24- 38 cm long, 0.8- 1 cm wide, prophyll not seen, peduncular bracts several but only 2 preserved, c. 77 and 82 cm long, c. 9 cm wide, purplish, covered in red brown tomentum, rachis c. 48 cm long; rachillae 9- 15 cm long, c. 0.5 mm wide; pedicel 0.6- 1.2 mm. Staminate flowers yellow, calyx connate for c. 0.4 mm, lobes 1.6 -2 ?x 0.8- 1 mm; petals free, 6.2- 6.5 ?x 4.5- 4.7 mm, with scattered minute red dots near the apex; stamens (6) 12, 2 opposite each petal, and 2 opposite each sepal, filaments 0.4- 0.8 mm, anthers c. 3.5 x 1.4 mm., pistillode minute. Pistillate inflorescence erect, branched to 1 order, peduncle 19- 25 cm long, c. 1.6 cmacross, yellowish, covered with red brown tomentum; prophyll c. 30 x 8 cm, pinkish, covered with red brown tomentum; peduncular bractsc. 85x 6 cm, ± equal in size, purplish-pink, abaxial surface densely covered in red brown tomentum in the upper part; rachis 30-35 x 1.5- 1.7 cm, yellow but sparsely to densely covered with red brown tomentum, with 6 . 18 rachillae; rachillae 35- 48 cm long, glabrescent, sinuous, pedicels 3.7- 5.2 mm long. Pistillate flowers yellow, sepals connate for c. 1.6 mm, lobes c. 0.8 ?x 0.7 mm; petals unequal, spathulate, coriaceous, 1.3- 6.5 x 4.5 - 5.4 mm; staminodes 12, minute; gynoecium c. 7.4 x 8 mm, gibbous, triloculate, stigmas recurved. Fruits blackish, subglobose, perianth persistent, stigmatic remains apical, 1.4- 1.6 x 1.5 - 1.6 cm, epicarp c. 0.8 mm thick, mesocarp 1.8 mm thick, spongy, endocarp spongy. Seeds 3; 1.3-1.4 x 0.7- 0.8 mm, seedcoat black, 0.1 mm thick; endosperm homogeneous. (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Materials Examined