Dypsis dracaenoides Rakotoarin. & J.Dransf., Kew Bull. 65(2): 280 (2010)

Primary tabs

no image available

Distribution

Map uses TDWG level 3 distributions (http://www.nhm.ac.uk/hosted_sites/tdwg/geogrphy.html)
Madagascarpresent (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A
Known only from Vondrozo forest, southeast of Madagascar. (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Habitat

  • Lowland humid forest and rather dry montane forest in the western part of Vondrozo. Common palm in valleys and on lower slopes; 550 - 600 m. (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Discussion

  • The dissected-leaved form of this beautiful species bears an uncanny resemblance to Dracaena (Dracaenaceae), hence the specific epithet. This new species is related to group 4 of Dypsis (Dransfield & Beentje 1995), which includes six palms of the southern part of the rainforest in Madagascar. The group includes multi-stemmed undergrowth palms with six equal stamens. The new species is immediately distinguished by its striking leaf polymorphism and inflorescence structure. (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Diagnosis

  • D. scottianae (Becc.) Beentje & J. Dransf. et D. macdonaldianae Beentje affinis sed foliis porrectis brevibus polymorphis, integris vel anguste dissectis differt. (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Conservation

  • Vunerable [VU (D2)]. Known only from an area about 15 km2, in the west of Vondrozo. About 100 mature individuals have been observed and the forest where it occurs is managed by the local population. Illegal logging and mining activities continue and increase the threats to this species, in particular through habitat loss and degradation. (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Common Name

  • Tavosy. (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Description

  • Clustering palm with 2 - 5 stems per clump, occasionally solitary, erect or sometimes leaning. Stems 2.5 - 4 m high, 0.8 - 1.5 cm diam.; internodes 0.8 - 4 cm long, covered with red scales in the distal part, proximal part with corky lenticels. Leaves 8 - 12 in the crown, forming a shuttlecock; sheath pale green, covered with red brown scales, 18.5 - 25 cm long, 1.5 - 2.2 cm wide, with auricles 5 - 6 × 0.6 - 1 cm; petiole absent or up to 4 cm long, occasionally densely scaly, adaxially flattened, abaxially rounded; rachis 16 - 38 cm long, tapering from c. 1 cm diam. at the base, adaxially flattened near the base, keeled towards the apex, abaxially angled, minutely scaly, blade coriaceous; lamina entire and deeply bifid or dissected; entire leaves 70 - 104 cm long, 10 - 16 cm wide, abaxially with scattered scales, ramenta very sparse, main veins 6 - 8 in each side of the rachis, apex dentate, lobe 55 - 80 cm, pinnate leaves with 8 - 9 very narrow leaflets on each side of the rachis, somewhat irregularly arranged, spaced at about 0.6 - 5.5 cm, proximal leaflets 41 - 60 × 0.5 - 0.7 cm, median leaflets 59 - 76 × 0.5 - 0.7 cm, distal multiplefold leaflets 59 - 70 × 1.3 - 2 cm, main veins 2 - 3, apices dentate, abaxial surface of leaflets with scatteredscales. Inflorescences interfoliar, pendulous to erect, branched to 2 orders; peduncle 50 - 68 cm long, 4 - 7 mm diam., brown puberulous; prophyll 18 - 20.5 cm long, 6.5 - 8 mm wide, inserted at 6 - 6.3 cm from the base of peduncle, 2-keeled, covered in scattered reddish- brown tomentum, open for 2 - 3.3 cm in the distalpart; peduncular bract 31 - 56 cm long, 4 - 7 mm wide,inserted at 7 - 10 cm from the base of peduncle,sparsely scaly with reddish-brown tomentum, apical beak c. 3 mm, split to 3.3 - 6.5 cm in the distal part; rachis 20 - 40 cm long, 0.4 - 0.6 cm wide, yellowish, covered with scattered red scales, with 4 - 9 first branched rachillae and 8 - 11 unbranched rachillae, proximal rachillae to 6 cm long with up to 4 rachillae; rachilla 7 - 16 cm long, c. 1 mm diam., minutely puberulous, triads distant. Staminate flowers with sepals 0.8 - 1.3 × 1 - 1.3 mm, imbricate, minutely scaly, triangular, keeled, slightly asymmetric; petals 2 - 2.1 × 1.6 - 1.8 mm, elliptic, valvate, striate, coriaceous; stamens 6, equal, filaments 0.5 - 0.7 mm long, c. 0.1 mm wide, anthers versatile, medifixed, elongate, 1.2 - 1.4 × 0.4 - 0.5 mm; pistillode obovoid, c. 0.4 mm high. Pistillate flowers with sepals 1.2 - 1.4 × 1.1 - 1.3 mm, minutely scaly, triangular, asymmetric; petals 2.2 - 2.4 × 1.1 - 1.4 mm, elliptic, striate, imbricate, coriaceous; staminodes minute; gynoecium c. 1.7 × 1 mm. Fruit not seen. (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Materials Examined

  • MADAGASCAR. Fianarantsoa, Vondrozo, Madiorano, 22°47 ?39 ?S, 47°11 ?18 ?E, 23 Oct. 2006, M. Rakotoarinivo et al. 312 (holotype K!; isotype TAN!); M. Rakotoarinivo et al. 316 (K!, TAN!). (M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010)A

Bibliography

A. M. Rakotoarinivo & J. Dransfield, New species of Dypsis and Ravenea (Arecaceae) from Madagascar in Kew Bulletin 65. 2010