Dypsis acuminum

From Palmpedia - Palm Grower's Guide
Jump to: navigation, search


Dypsis (DIP-sis)
acuminum (ah-koo-MIN-uhm)
Dypsis accuminum1.jpg
Madagascar. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.
Scientific Classification
Genus: Dypsis (DIP-sis)
Species:
acuminum (ah-koo-MIN-uhm)
Synonyms
None set.
Native Continent
Africa
Africa.gif
Morphology
Habit: Clustering
Leaf type: Pinnate
Culture
Survivability index
Common names
Lafaza (Manongarivo).

Habitat and Distribution

Dypsis acuminum is endemic to North Madagascar: Manongarivo and Marojejy Mountains.
Madagascar. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.
Montane forest; alt. 700-1900 m.

Description

Solitary, moderate palm. STEMS 4-6 m tall, 8 cm in diam.; internodes dark green to greyish, nodal scars forming obvious rings. LEAVES 5-6, arching, 1-1.5 m long; sheath 30-32 cm long, when flattened 8-10 cm wide, adaxially dark reddish purple, abaxially pale brown distally with scattered black scales, waxy, without ligules but with rounded shoulders; petiole 11-16 cm, proximally about 1.2 x 0.6 cm, distally 0.8-1.3 x 0.6-0.7 cm in diam., channelled with sharp edges, red-brown with blackish scales; rachis with dense to scattered blackish scales, in mid-leaf 0.6-1.2 x 0.6-0.7 cm in diam.; leaflets regular, about 30 on each side of the rachis, acuminate, proximal 35- 36 x 0.3-1 cm, median 27-39 x 1.2-1.8 cm (interval 1.5-3 cm), distal 6-30 x 0.3-1.4 cm, main veins 1, glabrous but for 3-4 scattered ramenta. INFLORESCENCE interfoliar at anthesis, infrafoliar in fruit, branched to 1 or 2 orders; peduncle 28-41 cm long, proximally about 2 x cm, distally 1.2 x 0.6 cm, glabrous; prophyll 30-35 cm long, borne at 6-9 cm above the base of the peduncle, with scattered scales but glabrescent, open for the distal 10 cm; peduncular bract inserted at 18-20 cm from the base of the peduncle, 36-37 cm long, split over its whole length or except for the distal 3-4 cm, beaked for 3-4 cm, with dense but scattered scales; non-tubular peduncular bracts 1-1.3 cm, near the apex of the peduncle; rachis 12-34 cm, with 15-18 unbranched first order branches, in the type with one of the branches bifurcate; rachillae 10-25 cm long, 2.5-4 mm in diam., glabrous, with quite dense triads, slightly sunken in pits; rachilla bract about 2 mm long, acute to acuminate. STAMINATE FLOWERS unknown. PISTILLATE FLOWERS only known from the young fruiting stage, with the sepals 2.8- x 3-4 mm; petals 3.5-5.2 x 4-6 mm; staminodes 0.5-1 mm; gynoecium probably about 4 mm high. FRUIT ellipsoid, 9-10 x 6-7 mm., rounded at apex; endocarp fibrous, with few anastomations. SEED ellipsoid, 8-8.5 x 5.5-6 mm, the base with a slight bump and a sub-basal depression corresponding to the embryo, the apex rounded; endosperm homogeneous. (J. Dransfield and H. Beentje. 1995)/Palmweb. Editing by edric.

The altitude on the type is indicated as 2000 m, but the highest point in the Manongarivo Mts., Antsatrotro, is 1876 m. This taxon is probably the same as D. onilahensis; only the branching pattern of the inflorescence is distinct, being much less branched. (J. Dransfield and H. Beentje. 1995)/Palmweb.

Culture

Cold Hardiness Zone: 10a

Comments and Curiosities

A rare species, which may well be the same as D. onilahensis. The Latin name means 'of the peaks'.

Conservation: Unknown. Only known from a single recent collection, but it is possible this taxon occurs on more high mountains of the north, most of which are not well known botanically.

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

Phonetic spelling of Latin names by edric.

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

Special thanks to Palmweb.org, Dr. John Dransfield, Dr. Bill Baker & team, for their volumes of information and photos.

Glossary of Palm Terms; Based on the glossary in Dransfield, J., N.W. Uhl, C.B. Asmussen-Lange, W.J. Baker, M.M. Harley & C.E. Lewis. 2008. Genera Palmarum - Evolution and Classification of the Palms. Royal Botanic Gardens, Kew. All images copyright of the artists and photographers (see images for credits).

Dransfield, J. & Beentje, H. 1995. Palms of Madagascar. Royal Botanic Gardens, Kew and The International Palm Society.


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

Banner1B
Back to Palm Encyclopedia


Retrieved from "http://palmpedia.net/wiki/index.php5?title=Dypsis_acuminum&oldid=135518"