Family:
Arecaceae Bercht. & J.Presl
Genus:
Ravenea H.Wendl. ex C.D.Bouché

Ravenea hypoleuca Rakotoarin. & J.Dransf.

This species is accepted, and its native range is Madagascar.

[KBu]

Rakotoarinivo, M. & Dransfield, J. 2010. New species of Dypsis and Ravenea (Arecaceae) from Madagascar. Kew Bulletin 65: 279. DOI: https://doi.org/10.1007/s12225-010-9210-7

Conservation
Critically Endangered [CR(B2a + b(iii); D)]. Rare species, known only from Vondrozo where fewer than 20 mature individuals have been seen in an Extent of Occurrence of 6.7 km2. Current threats are mostly related to habitat loss and degradation due to timber extraction.
Distribution
Known only from Vondrozo forest, southeast Madagascar.
Ecology
Lowland humid forest, valley bottoms or lower slopes; 550 – 600 m.
Morphology General Habit
Medium-sized solitary, dioecious palm
Morphology Leaves
Leaves 16 – 20 in the crown, porrect, marcescent, litter-trapping; sheath 60 – 110 × 10 – 15 cm, pale green, covered in thick white tomentum, margins disintegrating and fibrous; petiole 80 – 150 cm long, 3.5 – 4 × 1.5 – 2.5 cm in cross section, deeply channelled, margins sharp, covered in white to greyish tomentum; rachis 3.5 – 4 m long, in mid-leaf 2.5 – 2.8 × 1.8 – 2.3 cm in cross section, pale green, covered in thick white tomentum especially on the abaxial surface, keeled on the adaxial surface; leaflets stiff, regularly arranged in one plane, dark green, 52 – 58 on each side of the rachis, proximal leaflets 62 – 85 × 1.5 – 2.8 cm, median leaflets 102 – 116 × 2.4 – 2.8 cm, distal leaflets 16 – 37 × 1.2 – 2 cm, leaflets spaced 4 – 6 cm apart, abaxial surface with continuous white tomentum, transverse veinlets sinuous
Morphology Reproductive morphology Flowers
Flowers not seen Flowers not seen
Morphology Reproductive morphology Fruits
Fruits not seen.
Morphology Reproductive morphology Inflorescences
Pistillate inflorescence interfoliar, solitary, erect, branched to 1 order, 20 – 30 cm long, c.2.4 cm in cross section; prophyll and peduncular bracts not seen; rachis 10 – 17 cm long; first order branches 18 – 22; rachillae 28 – 42 cm long, up to 1 cm in cross section at the base; pedicel 3 – 5 mm high Inflorescences interfoliar, solitary Staminate inflorescence erect, branched to 2 orders; peduncle 24 – 30 cm long, c.1.5 – 3 cm in cross section, prophyll not seen, peduncular bracts c.73 cm long, c.14 cm wide, purplish, covered in thick white tomentum; rachis c.48 cm long; rachillae 12 – 20 cm long, c.2 mm in cross section; pedicel 0.6 – 1.2 mm
Morphology Trunk
Trunk 6 – 10 m tall, 15 – 20 cm diam., blackish brown, covered in sheath remnants in the upper part, c.25 cm in cross section
Note
Initially this was confused with Ravenea albicans because of the strongly discolorous leaflets but it differs in the presence of continuous brown scales on the leaf rachis, rather than striped and discontinuous, and the inflorescence branched to 2 orders in the staminate plants. Based on incomplete material, the palm is nevertheless distinct and should be searched for in good fertile state and also elsewhere. The species epithet reflects the discolorous leaflets.
Type
Madagascar, Fianarantsoa, Vondrozo, Madiorano, Rakotoarinivo 315 (holotypusK!; isotypus TAN!).

Native to:

Madagascar

Ravenea hypoleuca Rakotoarin. & J.Dransf. appears in other Kew resources:

Date Reference Identified As Barcode Type Status Has image?
Nov 2, 2006 Rakotoarinivo, M. [RMJ315], Madagascar K000525799 holotype Yes

First published in Kew Bull. 65: 300 (2010)

Accepted by

  • Govaerts, R.H.A. (2011). World checklist of selected plant families published update Facilitated by the Trustees of the Royal Botanic Gardens, Kew.

Literature

Kew Bulletin

  • Britt, A. & Dransfield, J. (2005). Dypsisdelicatula. Palms 49: 40 – 44.
  • Dransfield, J. (2003). Dypsisturkii. Palms 47: 26 – 30.
  • Hanski, I., Koivulehto, H., Cameron, A. & Rahagalala, P. (2007). Deforestation and apparent extinctions of endemic forest beetles in Madagascar. Biol. Lett. 3: 344 − 347.CrossRefPubMedGoogle Scholar
  • Hodel, D. R. & Marcus, J. (2004). The White Powder Dypsis: A new species from cultivation. Palms 48: 90 − 93.
  • IUCN (2001). IUCN Red List Categories and Criteria: Version 3.1. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, UK.
  • Moat, J. & Smith, P. (2007). Atlas de la végétation de Madagascar. Royal Botanic Gardens, Kew.
  • Rakotoarinivo, M. (2008). A remarkable Ravenea from the montane forest of Andilamena, Madagascar. Palms 52: 11 − 17.
  • ____ & Beentje, H. J. (1995). The Palms of Madagascar. Royal Botanic Gardens, Kew.
  • ____ & Marcus, J. (2002). Dypsis ‘stumpy’. Palms 46: 47 – 51.
  • ____, Rakotoarinivo, M., Baker, W. J., Bayton R. P., Fisher, J. B., Horn, J. W., Leroy, B. & Metz, X. (2008). A new Coryphoid palm genus from Madagascar. Bot. J. Linn. Soc. 156: 79 − 91.CrossRefGoogle Scholar
  • ____, Ranarivelo, T. & Dransfield, J. (2007). A new species of Beccariophoenix from the High Plateau of Madagascar. Palms 51: 63 − 75.
  • ____, Trudgen, M. S. & Baker, W. J. (2009). The palms of the Makira Protected Area, Madagascar. Palms 53: 125 − 146.

  • Herbarium Catalogue Specimens

    Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/

  • Kew Backbone Distributions

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

  • Kew Bulletin

    Kew Bulletin
    http://creativecommons.org/licenses/by-nc-sa/3.0

  • Kew Names and Taxonomic Backbone

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0