Dypsis simianensis

Dypsis (DIP-sis) simianensis (sihm-ee-ah-NEN-sis)
Manombo, Madagascar. Photo by Dr. Henk Beentje, Royal Botanic Gardens, Kew/Palmweb.
Scientific Classification
Genus: Dypsis (DIP-sis) Species: simianensis (sihm-ee-ah-NEN-sis)
Synonyms
None set.
Native Continent
Africa
Morphology
Habit: Clustering Leaf type: Entire bifid.
Culture
Survivability index
Common names
None.

Habitat and Distribution

Endemic to Madagascar. Mananara, Soanierana-Ivongo, Zahamena and Manombo. Lowland rain

Manombo, Madagascar. Photo by Dr. Henk Beentje, Royal Botanic Gardens, Kew/Palmweb.

forest to rather dry forest; steep to gentle mid slope, soils rocky; alt. 65-250 (-850) m.

Description

Clustering palm in tufts of 2-12 stems. STEMS 0.5-2 m long, 0.4-1 cm in diam., erect or curving; internodes 0.5-2 cm long, distally with reddish laciniate scales. LEAVES 5-15 in the crown, spreading, entire; sheath 4.5-6.6 cm long, pale yellow-brown with scattered reddish scales, densest distally, closed for 60-90%, with oblique opening and minute triangular ligules 2 mm high; petiole 0.5-6.6 cm long, 1.5-2 mm wide, adaxially flat, with a few scattered scales; blade dark green, narrowly triangular, acute at the base, 15-35 x 2.5-4.7 cm, the apex bifid for 2.1-4.2 cm, the apices of the lobes truncate and dentate and 1-1.2 cm wide, only the midrib prominent on both surfaces, with reddish scattered scales, the other veins faint, glabrous, about 9 on each side of the rachis. INFLORESCENCE interfoliar, erect to spreading, unbranched; peduncle 5.5-24 cm long, c. 1.5 mm in diam., proximally with a few scattered scales; prophyll 8-12 cm, borne at 2.5-4 cm above the base of the peduncle, 3 x 2 mm in diam., with a few scattered scales mainly on the narrow wings, split only in its distal 5 mm; peduncular bract inserted at 7-8 cm from the base of the peduncle, 4.5-13 cm long, with a few scattered scales, split only in its distal 5 mm; rachilla 5-16 cm long, about 2 mm in diam., glabrous or minutely puberulous, with distant superficial triads; rachilla bract entire, rounded. STAMINATE FLOWERS white; sepals 1.3-1.7 x 1.2 -1.3 mm, keeled, gibbous, rounded, ciliate; petals 1.7-1.8 x 1.1-1.4 mm, ovate, acute, striate, at anthesis hardly opening and leaving an opening of only 0.6 mm wide for the stamens; stamens 6, uniseriate, the filaments connate for 0.2-0.5 mm, in bud 1 mm long but rapidly lengthening at anthesis to about 2.5 mm, the antepetalous slightly wider than the antesepalous, anthers 1.2-1.4 x 0.5-0.6 mm, dorsifixed, the locules slightly divergent at the base; pistillode about 1.5 mm, narrowly ovoid, 0.8 mm in diam. PISTILLATE FLOWERS unknown except for very young buds. FRUIT unknown, except for the fibrous endocarp with almost free fibres. SEED about 8 x 6 mm, rounded at both ends, with homogeneous endosperm. (J. Dransfield and H. Beentje. 1995)/Palmweb. Editing by edric.

Cours 4192 is from higher altitude than the other specimens; it has very short inflorescences with shorter rachillae than usual. (J. Dransfield and H. Beentje. 1995)/Palmweb.

Culture

Clod Hardiness Zone 10a

Comments and Curiosities

A very handsome small palm, with entire, very narrow leaves with only a short notch at the tip. We have never seen the fruit, but this species would make an exquisite ornamental. The name comes from the type locality, which was slightly mis-spelt on the label. (J. Dransfield and H. Beentje. 1995)/Palmweb.

Conservation: Endangered. Known from a limited number of sites, with the individual populations consisting of few individuals. Recent collections are few; HB has seen a total of less than forty plants. (J. Dransfield and H. Beentje. 1995)/Palmweb.

NATURAL HISTORY: In Manombo HB photographed an insect visitor to the open male flowers, tentatively identified by Dr. Verdcourt as a Sphecoid wasp; it visited several open staminate flowers and inserted its mouth parts. One of the flowers of Beentje & Andriampaniry 4786 is much larger than the others (some 3.5 mm), and it proved to contain a 3 mm long white caterpillar; such galled flowers are of very common occurrence in undergrowth species of Dypsis, particularly in those species with three stamens. Male flowers are open when female buds are still minute. (J. Dransfield and H. Beentje. 1995)/Palmweb.