Ravenea albicans (Jum.) Beentje, Kew Bull. 49: 663 (1994)

Primary tabs

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Content

Introduction

  • This tree is immediately recognizable by the white undersides of the leaflets, and the "zebra-striping" on the leaf rachis. Despite these outstanding characters, it remained uncollected for about seventy years after the first collection by Perrier. The Latin name refers to the white leaflet undersides. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Distribution

Map uses TDWG level 3 distributions (https://github.com/tdwg/wgsrpd)
Madagascar present (World Checklist of Arecaceae)B
NE Madagascar; the protologue says common between Fenerive (Fenoarivo) and Antalaha, but does not cite any specimens for this distribution. The palm is certainly not common nowadays. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Discussion

  • We believe that this species only flowers and fruits at intervals, i.e. not every year, since all the trees we checked in Mananara Biosphere Reserve over a period of two years were sterile, with only ancient inflorescences. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Biology And Ecology

  • Moist forest at 100-400 m alt.; steep mid slope on ultramafic soil. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Conservation

  • Endangered. Only known from two recent localities, in one of which where we counted 40 trees with trunks, about a hundred young ones without trunks, and several seedlings. The distribution area was very limited. The second locality only came to light when the book was going to press. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Common Name

  • Hoza-tsiketra (Betsimisaraka) (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Uses

  • Heart edible. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Description

  • Slender undergrowth palm; trunk 3-6 m, DBH up to 11 cm, covered in marcescent, litter-trapping sheath bases. Leaves c. 8 in the crown, porrect, 3-4 m long; sheath c. 72 cm, with brown-velvety tomentum over green; petiole 0-34 cm, proximally about 5 x 4 cm across, distally 3.7 x 3.3 cm across, canaliculate; rachis c. 3 .7 m long, in midleaf 2-2.2 cm wide with 8 mm wide keel, with transverse ('zebra') striping especially abaxially; leaflets stiff, in one plane, 45-47 on each side of the rachis, the proximal 62-65 x 2.2-2.5 cm, median 75-83 x 6.6-7.2 cm (the protologue gives 50-60 x 2-2.5, but in the type the apices are broken off and the leaflets are folded) (interval 4.5-5 cm), distal 20-25 x 0.8- 1.5 cm; abaxially with continuous white tomentum. Staminate inflorescences solitary, interfoliar, branching to 1 order, hardly exserted, mostly hidden among sheaths and leaf remnants; peduncle distally 12 x 6 mm, dense white-puberulous; with 3(-4?) bracts, the first being destroyed at anthesis, the ones seen 25 cm, 30 cm, 32-35 cm; rachillae 5-8 cm long, 2.5 mm across; calyx reduced to 3 small triangular teeth < 2 mm; petals elongated, triangular and acuminate, 5.5-6.5 mm, free or hardly connate at the base; episepalous stamens with large filament, appearing free among the spread petals; epipetalous stamens with filament connate to inner side of petals, the anthers therefore appearing sessile. Pistillate inflorescences solitary, interfoliar, erect, 126-150 cm, branched to 1 order; peduncle 94-120 cm, proximally 2.5-3.4 x 1.2-1.7 cm across, distally 1.5 x 0.8 cm; prophyll c. 18 x 7.5 cm; peduncular bracts seen 27 cm, 34 cm, 46 cm; rachis 8-12 cm; rachillae 8-13 in number, 17-29 cm long; pedicels 1- 2 mm; flowers unknown. Fruit unknown. Eophyll bifid, with the characteristic white abaxial surface of the leaflets. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Materials Examined

  • Masoala, presumably near Antalaha, no date (stam.), Perrier 11939 (Holotype P); Mananara: W of Antanambe, April 1992 (old pist.), Beentje et al. 4630 (K), 4643 (K, MO, P, TAN); idem (seedling), Beentje et al. 4644 (K); idem, Oct. 1994 (dead pist.), Beentje & Dransfield 4812 (K, TAN), and (seedl.), 4814 (K, TAN). (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Bibliography

    A. Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar
    B. World Checklist of Arecaceae