Ravenea albicans

Ravenea (rah-vehn-EH-ah) albicans (AL-bih-kanz)
Antanambe, Madagascar. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.
Scientific Classification
Genus: Ravenea (rah-vehn-EH-ah) Species: albicans (AL-bih-kanz)
Synonyms
None set.
Native Continent
Africa
Morphology
Habit: Solitary Leaf type: Pinnate
Culture
Survivability index
Common names
Hoza-tsiketra (Betsimisaraka). White Majesty Palm.

Habitat and Distribution

Ravenea albicans is endemic to Northeast Madagascar; the protologue says common between

Makira - Madagascar (2016) - East Coast of Madagascar. Photo by "Olivier Reilhes"

Fenerive (Fenoarivo) and Antalaha, but does not cite any specimens for this distribution. The palm is certainly not common nowadays. Moist forest at 100-400 m alt.; steep mid slope on ultramafic soil.

Description

Slender solitary undergrowth palm; trunk 3-6 m high, up to 11 cm in diam. at breast height, covered in marcescent, litter-trapping sheath bases. Leaves, about 8 in the crown, porrect, 3-4 m long; sheath about 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 about 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. (J. Dransfield and H. Beentje. 1995)/Palmweb. Editing by edric.

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. (J. Dransfield and H. Beentje. 1995)/Palmweb.

Culture

Warm, sheltered, and moist. Likes a very light, open mix and heavy shade. Very slow growing. Cold Hardiness Zone: 10a