Dypsis trapezoidea J.Dransf., Palms Madagascar : 284 (1995)

Primary tabs

no image available

Introduction

  • A beautiful species known at present only from the isolated hill, Vatovavy, southwest of Mananjary. First collected by Bosser, we had initially included it within the variation of D. thiryana, but newly collected specimens show abundant differences between the two. This would be a beautiful ornamental. The species name refers to the leaflets that are almost trapezoid in outline. (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Distribution

Map uses TDWG level 3 distributions (http://www.nhm.ac.uk/hosted_sites/tdwg/geogrphy.html)
Madagascarpresent (World Checklist of Arecaceae)B
Known only from Vatovavy, Ifanadiana. (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Discussion

  • Because of the praemorse leaflets this species appears very similar to D. thiryana. It can be distinguished by the consistently solitary habit, the sparse evenly distributed scales on the sheaths (rather than thick patchy scales), the much longer petioles, the wider, almost trapezoid leaflets and the more numerous but much shorter rachillae that are shorter than the inflorescence rachis (rather than being few, and much longer than the rachis). The mature fruit is also more or less twice the size of that of D. thiryana. (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Diagnosis

  • Statura et habitu solitario foliolis praemorsis D. thiryanae affinis sed petiolo longiore, foliolis latioribus, inflorescentiae rachidi rachillas breviores aequanti vel excedenti et fructu duplo-majore differt. (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Biology And Ecology

  • Steep rocky slope at foot of cliff, primary lowland forest. (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Conservation

  • Critical. Single-site locality; site (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Common Name

  • Not recorded. (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Uses

  • Not recorded. (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Description

  • Solitary slender palm of forest undergrowth. STEM to 1.2 m tall, c. 8-12 mm diam. at the base, c. 4-7 mm diam. distally, often conspicuously stilt-rooted at the base, dark grey brown and vertically cracked at the base, dull green distally, internodes 8-18 mm with scattered dark brown scales, nodal scars c. 1-2 mm wide. LEAVES c. 7 in crown; sheaths 5-6.5 cm long, c. 1-1.2 cm diam., dull green with scattered evenly spaced thin brown scales, auricles absent; petiole 9-19 cm long, c. 2 mm wide, densely silvery scaly, especially when newly emerged; rachis 21-36 cm, scaly as the petiole; leaflets c. 7-10 on each side of the rachis, mostly arranged in pairs, somewhat trapezoid in outline, with conspicuous praemorse tips, basal leaflets with proximal margin 5.5-6 cm, distal margin 7-9 cm and praemorse margin 0.8-2 cm; mid-leaf leaflets with proximal margin 6.5-8 cm, distal margin 7-11 cm and praemorse margin 2-3 cm; apical leaflet pair much shorter than the rest with proximal margin 3.5-4 cm, distal margin 2.5-3 cm and praemorse margin 2-3.5 cm; leaflets drying pale green, adaxially with scattered brown punctiform scales, abaxially covered with dense white punctiform scales, abaxially also with a band of grey indumentum along the proximal and distal margins. INFLORESCENCE interfoliar, much shorter than the leaves, branched to 1 order; peduncle 7-12.5 cm, c. 2 mm wide, densely covered with brown scales; prophyll 9-10 x 0.4-0.6 cm, sparsely scaly; peduncular bract exceeding the prophyll by 4-5 cm; rachis 5-8 cm, densely scaly as the peduncle; rachillae 5-6 (-8), equalling or shorter than the rachis, diverging at right angles, at maturity c. 3.5-5.5 cm, much shorter when newly emerged, c. 1.5 mm diam., sparsely papillose and scaly, bearing triads c. 1-4 mm distant, rachilla bracts round-ed-triangular, c. 1 mm high. STAMINATE FLOWER buds (still immature) rounded, c. 1.2 mm diam.; sepals rounded, imbricate, irregularly keeled, c. 0.8 x 0.8 mm, margins sparsely scaly; petals triangular, 0.9 x 0.7 mm; stamens 6, immature anthers 0.5 x 0.2 mm; pistillode columnar. PISTILLATE FLOWERS, only very young buds known. Mature FRUIT cherry-red, fusiform, 18 x 6 mm. SEED c. 15x 4 mm, endosperm homogeneous. (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Materials Examined

  • Mananjary: Mt. Vatovavy, Nov. 1994 (buds, fr.), Dransfield et al. JD7512 (Holotype K; isotypes AAU, BH, MO, NY, P, TAN). idem, Jan. 1964, Bosser 18905 (P, TAN). (J. Dransfield & H. Beentje, The Palms of Madagascar. 1995)A

Bibliography

A. J. Dransfield & H. Beentje, The Palms of Madagascar. 1995
B. World Checklist of Arecaceae