Ravenea dransfieldii

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Floribunda Palms, Hawaii.
Ravenea dransfieldii
Ravendransfel.jpg
Bill Austin's Garden, Big Island.
Scientific Classification
Genus: Ravenea
Species: dransfieldii
Synonyms
None set.
Native Continent
Africa
Africa.gif
Morphology
Habit: Solitary
Leaf type: Pinnate
Culture
Survivability index
Common names
Anivo (Betsimisaraka-Masoala); Ovotsarorona (Betsimisaraka-Betampona); Lakatra (for stam.) and Lakabolavo (for pist.) (Tanala).


Habitat and Distribution

Madagascar. East Madagascar: between Marojejy Mts. and Ifanadiana. Moist forest, on slight to steep slope or hill crest; 425-1700 m.

Description

Medium-sized palm, the trunk 4-7 m, Diam. head high 10.5-18 cm (diameter near crown 9.5-15 cm); bark pale brown, scars 2.5-6 cm, internodes 4-7 cm; wood black, extremely hard; wounds in bark bleed watery fluid. Base of crown bulbous, 24 cm across. Leaves 11 - 17 in crown, porrect, straight, held on edge in distal half; sheaths open, 45-63 x 15-20 cm, pale or bright green, covered in white or brown tomentum, glabrescent, the margins with reflexed fibre spines; petiole absent; rachis 330-435 cm long, 4.3-13 x 1.2 -6 cm across proximally, 2-2. 8 x 1-1.2 cm in the middle part, here either deeply canaliculate or with a keel c. 5 mm wide, green with scattered brown scales; leaflets dark green, 70-84 on each side of the rachis, the lowermost reflexed or pendulous (and grouped in 3), the rein margin with almost woody dentiform excrescences; other leaflets in one plane or slightly pendulous, pale or dark green, leathery, ramenta lacking, the proximal (65) 95- 120 x 1.3-4.7 cm (and once with the proximal 2 pairs distant by 30 cm from the more distal pairs), median 72-100 x 3-5 cm (interval 3-4 cm), distal 11-37 x 0.5-3 cm, the top pair connate for 1/5, the rachis continuing past the distal pair for > 1 cm; ramenta very few or none; small sinuous transverse veinlets visible in dried material. Staminate inflorescence solitary, erect, c. 126 cm, branched to 2 orders with erect rachillae; peduncle 44-66 cm long, distally 0.5-2.5 x 0.5-1.25 cm; prophyll unknown; peduncular bracts about 42 cm, 52 -66 x 9 cm, 97 - 140 cm, 100- 139 x 8 cm; non-tubular peduncular bract 4.7 – 7. 9 x 0.1 -0.8 cm; rachis 30-50 cm with 1-6 branched and c. 50 unbranched first order branches; rachillae 18-35 cm long, c. 1.3 mm across; pedicels 1.5-3 mm; bracteole 2.3-2.8 mm, connate for 0-1 mm; flowers foetid or sickly scented, cream-coloured becoming grey- brown, becoming hot at anthesis, not abscising but becoming marcescent; petals very quickly deliquescing, leaving included fibres; calyx connate for 1.8-3 mm, 2.3-2.6 mm across, free lobes triangular, acute, 0.8- 1. 7 x 0.8- 1.2 mm; petals free, narrowly ovate, acute, 4.5-6.5 x 1. 5- 2.5 mm; anthers 3 – 3.3 x 1- 1.3 mm, the filaments 0.2 mm (anther inserted 0.5 mm up the petal when antepetalous) to 0.6- 1.6 mm (antesepalous); pistillode 0.3-0.7 x 0.3-0.5 mm. Pistillate inflorescence solitary, interfoliar, branching to one order, erect, largely obscured by the leafsheaths; peduncle c. 26 cm long, proximally 3 x 1. 4 cm, distally 2.5-2.8 x 1. 3 cm across' prophyll 28 x 9 cm, white, membranous; peduncular bracts almost fleshy, pale cream-coloured when fresh, becoming brown, the proximal small (36.5-49 x 3.7-6.5 cm), pubescent externally, glabrous internally, the upper two large, (43 +)-72, (58 +)-74 cm; rachis c. 18 cm long, the rachillae many, tightly packed, appressed-erect, 9- 5-27 cm long, 1.5 - 2 mm across; pedicels 1.5 - 8 mm, with an 80% connate bracteole of 1.5-3.5 mm long; bracteoles 15 x 0.5 cm; flowers foetid or sickly-scented, cream-coloured becoming grey-brown, becoming hot at anthesis, not abcising but becoming marcescent; petals very quickly deliquescing, leaving included fibres; calyx connate for 1 mm, 1 - 5 mm across, free lobes 1-1. 5 x 1.3 mm; petals 4.2-8.5 x 2.3-3.2 mm, c. 1 mm thick; ovary 3.5-4.2 x 2.3-3 mm; staminodes six, 1.5 mm long. Fruit orange (fide Humbert), ovoid or ellipsoid, 15-20 x 12-15 mm, one-seeded; stigmatic remains subbasal; seed ellipsoid, 15 x 10 mm, seed coat black, 0.2 mm thick, with outer sclerified pericarp-like black layer.

Culture

Shady, sheltered, and moist.

Comments and Curiosities

This rare species was one of the "links" between Ravenea and Louvelia. It is a rather short palm of the middle story of rain forest. The basal leaflets hang down limply. The flowers are very fleshy and have a musty or sickly smell.

Polinnation: Flowers visited by beetles.

Conservation: Vulnerable. Population numbers are low at every site. The Ifanadiana population is under threat of destruction.

Uses: Apex said to be poisonous by some, but also reports of palm-heart being eaten; used in hat-making.

This is a tillering palm, it exhibits saxophone style root growth (it has a heel), keep top third of heel above soil elevation!.

External Links

References

Special thanks to Geoff Stein, (Palmbob) for his hundreds of photos, edric.


Many Special Thanks to Ed Vaile for his long hours of tireless editing and numerous contributions.

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