Dypsis angusta Jum., Ann. Inst. Bot.-Géol. Colon. Marseille , III, 6(1): 34 (1918)

Primary tabs

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Introduction

  • This is a small palm of the undergrowth of low crown forest occurring on the isolated peak of Vatovavy, at the edge of the coastal plain south of Mananjary. We refound it in November 1994. The Latin name means narrow, presumably in reference to the narrow leaflets. (J. Dransfield & H. Beentje, 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
East Coast, only known from the Ifanadiana area and Farafangana. (J. Dransfield & H. Beentje, Palms of Madagascar. 1995)A

Discussion

  • The type, Perrier 11976, from Vatovavy, has leaves with two to three leaflets on each side of the rachis. A recent collection from Vatovavy (Dransfield et al. JD7514) has an inflorescence larger than that of the type and with up to 20 rachillae. Collections made at Manombo (Beentje 4511) have eight to nine pairs of leaflets. We are including the latter collection in D. angusta because of the manifest similarities in inflorescence structure and leaf texture and colour. All four collections cited are from the central part of the east coast, yet they are rather heterogeneous, and we are not completely certain that they all represent one species. Until more material is collected this will remain a poorly known species. (J. Dransfield & H. Beentje, Palms of Madagascar. 1995)A

Biology And Ecology

  • Rain forest; 45-500 m. (J. Dransfield & H. Beentje, Palms of Madagascar. 1995)A

Conservation

  • Endangered. Only known from three sites, in which population numbers are low. None of these sites is protected. (J. Dransfield & H. Beentje, Palms of Madagascar. 1995)A

Common Name

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

Uses

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

Description

  • Slender clustering undergrowth palm. STEMS to 2 m or more tall, 5-10 mm diam., internodes to 9 cm long near the stem base, decreasing to 0.8-1.2 cm long near the crown, basally bearing abundant chocolate-brown caducous scales, glabrescent distally; crown with c. 4-6 leaves; leaf-sheaths 5-7 cm long, forming a crownshaft, striate, covered with caducous chocolate-brown scales, auricles scarcely developed or to 10 x 2 mm, membranous. LEAF to 43 cm long including petiole; petiole 3-12 cm long, 1.5-3 mm wide, ± triangular in cross-section, bearing sparse caducous pale and chocolate-brown scales; rachis 10-29 cm long, bearing 2-3 or 7-9 (see notes below) narrow, ± approximate, regularly arranged leaflets on each side; leaflets 9-30 x 0.7-2.1 cm, drying dark or pale Dypsis angusta. Inflorescence, Vatovavy (Dransfield & Beentje JD7514) greenish brown, composed of 1-4 folds, acuminate, adaxially with sparse minute punctiform scales, abaxially minutely roughened and with scattered punctiform scales. INFLORESCENCE interfoliar, shorter than the leaves, sparsely branched to 1 (-2) orders, basal 1 or 2 first order branches sometimes branched; peduncle 7-18 cm long, c. 2.5 mm diam., densely covered in caducous, dark brown laciniate scales; prophyll 12-16 x 0.7-1cm, bearing scattered pale or dark brown scales; peduncular bract 8-10 x 0.7-1 cm, similar to prophyll; rachis 4-9 cm long, c. 2.5 mm diam., densely scaly as the peduncle; rachillae 2-20, rather short and stocky, 2-7 cm long, c. 1.5-2.5 mm diam. bearing rather dense chocolate-brown scales; triads c. 1 mm distant in newly emerged inflorescence, eventually c. 3 mm distant. STAMINATE FLOWERS c. 1 mm diam.; sepals broad, rounded, imbricate, somewhat striate, c. 0.7 x 0.7 mm; petals rounded triangular, 1 x 0.8 mm; stamens 3, antepetalous, filaments 0.8 x 0.3 mm, anthers 0.4 x 0.2 mm; staminodes tooth-like, 0.3 x 0.2 mm; pistillode very small. PISTILLATE FLOWER bud immature, c. 1 x 1 mm; sepals rounded, imbricate, c. 1 x 1 mm; petals triangular, c. 1 x 0.6 mm; staminodes 3, minute; immature ovary c. 0.4 mm diam. Mature FRUIT unknown. (J. Dransfield & H. Beentje, Palms of Madagascar. 1995)A

Materials Examined

  • Mananjary: Mt. Vatovavy, Aug. 1911 (fl.buds), Perrier 11976 (holotype P); idem, Nov. 1994 (fl.), Dransfield et al. JD7514 (K, TAN). Farafangana: Manombo Reserve Special, Nov. 1991 (dead infl.), Beentje 4511 (K, TAN). Fianarantsoa: Amfamahirana, Nov. 1963 (fl.), Bosser 18300 (K, P). (Plate: see next page). (J. Dransfield & H. Beentje, Palms of Madagascar. 1995)A

Bibliography

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