Ravenea delicatula

Family: Arecaceae    Palmier

Nom commun: aucun connu

zone de rusticité: 10a     Voir les cartes des zones de rusticité pour le Royaume-Uni et les États-Unis

A clump-forming, small, water-loving, moderately fast growing, dioecious, forest understorey palm. Not known in cultivation, rare in the wild. It has smooth, grey stems, 4.5 m. (15 ft.) tall, 1.2 cm. (0.5 inch) diameter with no obvious leaf scars, and small segmented, pinnate (feather) leaves, 0.3 m. (1 ft.) long, 0.18 m. (0.6 ft.) wide, light green above and beneath.

Stems solitary or clustering, occasionally branched. This plant is suitable as a houseplant or conservatory plant.

Ravenea delicatula can tolerate close to freezing conditions. But low temperatures are best avoided. It naturally occurs in wet rainforest or seasonally wet forest in low montane locations. In this type of natural environment temperature fluctuations are slight, and this palm prefers a constantly cool or mild climate with little temperature difference between day & night, and Summer & Winter. Under extreme cold conditions we recommend you keep this palm as dry as possible, and well wrapped up.

Identification:
Solitary or clustering, dioecious, pleonanthic palm. Stem 4-5 m tall, occasionally branching, procumbent, 1.2-1.7 cm diam. (near crown 0.7-0.8 cm), internodes 0.4-6 cm, scars 0.2-0.4 cm, surface smooth, sheath remnants occasionally persistent. Leaves 6-9 in crown, spiral, arching; sheath 6-15 1.6-4.4 cm, densely covered with red-brown to grey tomentum, marginal parts disintegrating, the tomentum persistent; petiole 4.3-8.6 cm long, proximally 0.2-0.1 cm, distally 0.1-0.1 cm, channelled, slightly convex abaxially, sparsely tomentose, the tomentum deciduous; rachis 21.6-33 cm, in mid-leaf 0.1-0.1 cm, medially sharply keeled, triangular, abaxially with red brown indument but soon glabrescent; leaflets 17-25 on each side of the rachis, 3 or 4 in each group, lanceolate, held in different planes, proximal 8.7-10.8 0.2-0.3 cm, median 11.8-14 0.3-0.4 cm, distal 9.6-10.6 0.2-0.4 cm, top pair with 2 or 3 main veins. Staminate inflorescence interfoliar, multiple in 3s or 4s, the central ones maturing first, individual inflorescence branching to 1 order, peduncle very slender, 4.5-11.8 cm long, with red brown tomentum; common prophyll 1.1-1.4 0.8-1 cm, prophyll 3.2-9.6 0.4-06 cm, keeled, with dense red brown tomentum; peduncular bracts 2, the same size, densely pubescent with red brown tomentum, 15.4-17.2 1.1-1.3 cm, thickness less than 1 mm, opened at 5.8-7.6 cm from the base of peduncle; rachis 2.7-4.3 cm, glabrous, with ca. 6-9 rachillae, rachis bract 0.7-0.1 cm; rachillae 4.2-6.4 cm long, slightly zigzag, flowers 0.4-0.7 cm distant, pedicel ca. 0.5mm. Staminate flowers, sepals connate at the base for 0.4-0.6 mm, free parts 0.6-0.8 0.8-1 mm, acute; petals 6.2-8 1.8-2.6 mm, imbricate; stamens 6, uniseriate, filament 0.8-1.2 mm (3 epipetalous, adnate for 0.6-0.8 mm), cylindrical; anthers basifixed introrse, 2.4-3 0.9-1.2 mm; pistillode 0.4 0.6 mm. Pistillate inflorescence interfoliar, solitary, branched to 1 order, 10.2-28.8 cm long, with red brown tomentum; prophylls 2, first 2.4-2.7 0.3-0.4 cm, second 5.1-21.2 1.2-1.8 cm, densely tomentose; peduncular bracts 2, 19.2-22.3 1.1-1.6 cm, thickness less than 1 mm, with dense red brown tomentum; rachis 2.9-4.7 cm, glabrous, with ca. 5-9 rachillae, 0.9 0.1 cm; rachillae 3.9-4.8 cm long, slightly zigzag, flowers 0.4-1.1 cm distant, pedicel c. 0.5mm. Pistillate flowers, sepals connate at the base for 0.8-1 mm, free parts 1.4-2 1.1-1.4 mm, acute; petals triangular, acute, 6.8-8.5 2.2-3.1 mm; staminodes 6, triangular, ca. 1.40.3 mm; ovary ovoid, 3.5-4 1.4-1.6 mm, stigmas 3. Fruits not seen.

Informations générales:
Toamasina, Analanjirofo 875 m. alt.

Distribution:

Originaire de, Madagascar

Toamasina, Analanjirofo 875 m. elevation.

Localisation: Madagascar (-16.991293°N, 48.841782°E)

Observations
La carte peut ne pas représenter précisément la répartition naturelle. (Les marqueurs indiquent les données observées).


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