Dypsis lokohensis J.Dransf., Palms Madagascar : 350 (1995)

Primary tabs

no image available

Content

Introduction

  • A slender palmlet of the undergrowth of montane forest. Because of its inflorescence structure and staminate flower size and shape, this species has the general appearance of members of the genus that were previously included in Neophloga, and had previously been misidentified as D. (Neophloga) lutea and Neophloga lanceolata. However, there are only three stamens in the staminate flower, and they are of an extraordinary form. The slender filaments end in a bifid connective, each arm reflexed and bearing a single short pendulous anther. The overall form thus approaches that of the stamens of some members of the New World palm genus Geonoma (Tribe Geonomeae). The Lokoho River, after which the palm is named, drains the whole southern half of the mas sif of Marojejy. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Distribution

Map uses TDWG level 3 distributions (https://github.com/tdwg/wgsrpd)
Madagascar present (World Checklist of Arecaceae)B
Madagascar, only known from Marojejy. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Discussion

  • The two specimens that make up the Humbert collection differ greatly in leaf dissection, yet they both bear the same collector's number. In one the leaf blade is entire bifid, in the other it is divided into irregularly arranged leaflets. However, details of indument and texture are identical. Cours 3243 from Ambatosoratra, is more robust; it has a pinnate leaf with subregular leaflets. Ambatosoratra lies at 14° 34á S 49° 44á E on the eastern slopes of the Marojejy Massif. The most recent collections have all been made on the eastern slopes of Marojejy, and vary in size and leaf dissection. Dransfield et al. JD6396 (K, TAN) from near Ambanizana on the Masoala Peninsula keys to this species but does not have the same texture; unfortunately, the available material does not have flowers and it is not possible to match the specimen with more certainty. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Diagnosis

  • Palma gracilis, foliis integro-bifidis vel pinnatis, inflorescentia 1- (rare 2) ramosa, rachillis paucis (4-9), pendulis, floribus staminatis triandris, staminibus antesepalis, connectivo valde bifido antheris pendulis distinctissima. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Biology And Ecology

  • Humid lowland and lower montane rain forest on steep slopes; 400-1200 m. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Conservation

  • Vulnerable. Only occurs in a restricted area, though there is some protection. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Common Name

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

Uses

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

Description

  • Slender clustering undergrowth palm. STEM to 3 m tall, 6 -15 mm diam., internodes 5-14 mm long with scattered caducous brown scales, nodal scars prominent. LEAVES 4-9 in crown; sheaths 6-12 cm long, c. 7-15 mm diam., longitudinally striate and bearing scattered caducous dark brown scales, sheath mouth lacking auricles; petiole 2-9 cm long, c. 1-3 mm diam., ± triangular in cross section, bearing sparse scattered dark brown scales; lamina entire bifid or divided into 3-9 subregular to grouped leaflets on each side of the rachis, rachis (or costa) 8-33 cm long, sparsely dark brown scaly; entire bifid lamina to 20-24 cm, divided to 65%, with lobes 14-15 cm long, 3.9-4.4 cm wide at widest point, tapering gradually to shallowly lobed tips, the apical cleft to 13 cm deep; pinnate leaf with leaflets subregular or grouped irregularly, somewhat sigmoid, the basal 4-30 x 0.3-4.5 cm, the subapical to 14-25 x 2-4 cm, the apical pair 10-17 x 1.8-6 cm, apically shallowly lobed; both lamina surfaces bearing minute brown punctiform scales along main ribs and veins. INFLORESCENCES interfoliar at first, apparently becoming infrafoliar, ± porrect, branching to 1 (or very rarely 2) orders; peduncle 12-32 cm long, 1-2 mm diam., sparsely scaly; prophyll 7-25 x 0.4-0.7 cm, apically irregularly laciniate, abaxially sparsely scaly; peduncular bract 18-20 x 0.5-0.7 cm, deciduous; rachis 3-6 cm, densely scaly when young; rachillae 4-9, somewhat curved or flexuous, 7-23 cm, densely scaly when young; triads borne ± superficially, c. 1 mm distant, rachilla bracts minute. STAMINATE FLOWERS c. 2 x 2 mm; sepals rounded triangular, abaxially keeled, c. 1x 1 mm; petals 2 x 1.3 mm, ovate-oblong, with triangular tips, striate; stamens 3, antesepalous, filaments elongating to 2 x 0.3 mm, pale, connectives tanniniferous, dark, bifid with pendulous arms to 0.5 mm, anthers pendulous and divergent on the connective arms, 0.4 x 0.2 mm; staminodes absent; pistillode conical, c. 0.5 mm high. PISTILLATE FLOWERS ovoid, c. 1.8 x 1.6 mm; sepals 1.1 x 0.9 mm, imbricate, rounded; petals 1.2 x 0.8 mm, imbricate basally, triangular valvate distally; staminodes 3, minute, dentiform; ovary 1.1 x 0.4 mm, ellipsoid. FRUIT only known in very immature state. (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Materials Examined

  • Andapa: Marojejy, trail to Marojejy Est from Mandena, above Camp 2, Nov. 1989 (fl.), Dransfield et al. JD6751 (K, TAN); (fl.), JD6752 (K, TAN); (fl.), JD6759 (Holotype K; isotypes P, TAN); Valley of the Lokoho, Mt. Ambodilaitra, north of Andranomiforitra and Belambo, March 1949 (fl.), Humbert 23275 (P); Ambatosoratra, Jan. 1949 (fl.), Cours 3243 (K, P); Col d'Andapa, Route de Sambava, April 1970 (fl.), Bosser 20114 (K, P). (Dransfield, J. & Beentje, H. 1995: The Palms of Madagascar)A

Bibliography

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