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This species is accepted, and its native range is W. Madagascar.
A specimen from Kew's Herbarium

[KBu]

Wilkin, P., Andrianantenaina, W.P. et al. (2008). The species of Dioscorea L. (Dioscoreaceae) from Madagascar with campanulate tori, including a new species from Eastern Madagascar. Kew Bulletin 63: 583. https://doi.org/10.1007/s12225-008-9079-x

Conservation
Least Concern (LC) (IUCN 2001). It is conceivable that local problems of over-exploitation may occur in populations of this very popular edible yam species.
Distribution
Widespread in western Madagascar, from Toliara North to Antsiranana.
Ecology
Found in deciduous forest, usually in open areas or forest margins. Tolerant of disturbance to some degree; it can be found in “islands” of shrubby growth in grassland. On sandy, calcareous and lateritic soils; 10 – 800 m a.s.l. It appears to be extensively managed in places; regular tuber extraction and replanting of the crown is said to increase plant density.
Morphology General Habit
A twining vine to about 10 m in height, stems annual from a fleshy tuber
Morphology General Indumentum
Indumentum of colourless hairs present on very young axillary buds, sometimes on cataphylls, pedicels and leaf lower surface (especially veins), hairs appearing multicellular, 0.15 – 0.3 mm long, often dense on axillary buds, sparse elsewhere, colourless modified hairs of crystalline appearance present on the veins of the lower leaf blade surface, to 0.2 mm long, flattened-deltoid, flattened-semicircular or denticular to cylindric, claviform or appressed-linear, sometimes forming elongate ridges along the veins, very dense to very sparse but always present, very small crystalline modified hairs also on leaf margins
Morphology General Spines
Lateral nodal flanges/spines (“stipules” of Burkill 1960) absent, but nodes often swollen, most visible near stem base
Morphology Leaves
Leaves alternate, blade 1.8 – 9.8 × 1.3 – 8.6 cm, ovate to broadly so or orbicular or narrowly ovate or lanceolate, especially on fertile shoots, chartaceous to thinly so, mid-green above, paler below, sometimes with an irregular white marking in the centre of upper surface, especially in seedlings, or with white variegation along the main veins, sometimes drying greyish below (e.g. Grève 135); margins entire or rarely very weakly lobed, base cordate, often hippocrepiform, not auriculate or lobed, sinus 2 – 22 mm deep, apex 3.5 – 18 mm long, acuminate with a 1 – 3.5 mm long, narrowly deltoid, brown forerunner tip; veins 3 or 5 to the apex, with a smaller, often bifid, vein to each basal lobe, primary venation prominent on lower leaf blade surface; petiole 1.2 – 8.6 cm long, often slender, terete but channelled above, sometimes with longitudinal ridges when dry, pale green, pulvinii often purple-hued
Morphology Leaves Cataphylls
Cataphylls present towards stem base and on main stems, c. 5 – 15 × 5 – 7 mm, broadly ovate, acuminate, purple-hued, thickened, sometimes verrucate, clasping branch bases
Morphology Reproductive morphology Flowers
Male flowers pedicellate, not scented, pedicels 0.9 – 2.5 mm long, obdeltoid in outline, very slender at base but 0.25 – 0.75 mm in diam. at apex, winged like axis, wing continuing around base of torus, floral bract 0.5 – 1.6 × 0.3 – 0.8 mm, narrowly ovate to elliptic, inserted at pedicel base, smaller towards cymule apex, thinly membranous; tepal whorls scarcely differentiated, inner slightly thicker and usually rounded at apex, tepals 6, 1.0 – 2.1 × (0.5 –) 0.8 – 1.6 mm, free, inserted on the rim of an urceolate, shiny pale green torus 1.3 – 2.4 × (0.6 –) 0.8 – 1.7 (– 2.0) mm (usually 1.1 mm or more in diam. in fully open flowers), fleshy, opaque in dried material, tepals ovate to very broadly so or broadly oblong-elliptic, apex obtuse to rounded, rarely acute, membranous to thickly so, pale green to yellow-green; stamens erect, filaments inserted towards centre of torus base, 1.2 – 2.2 mm long, filiform, slender, free or coherent (not fused) into a column, especially near apex, anthers 0.2 – 0.3 × 0.15 – 0.3 mm, oblong-elliptic, basifixed, introrse, yellow, filament apices often reflexed such that anthers are held in an outward-facing ring just above torus rim; pistillode erect, conical, c. 0.2 – 0.3 mm long, drying very dark brown, concealed by filament bases Female flowers subsessile, not scented; floral bract 1.4 – 2.6 × 0.6 – 1.2 mm, narrowly ovate to elliptic, acuminate, membranous, bracteole if present like bract but smaller, bract and bracteole clasping ovary base; ovary c. 3.2 – 5.3 mm long, 3-angled, elliptic to oblanceolate in outline, glossy dark green, darkest on angles, constricted at apex where torus is inserted (i.e. floral stipe very short or absent); tepal whorls scarcely differentiated, inner slightly thicker and usually rounded at apex, tepals 6, 1.3 – 2.1 × 0.7 – 1.1 mm, elliptic to ovate or oblong-elliptic, apex acute to rounded, spreading to recurved at maturity, membranous, pale yellow-green, inserted on an urceolate torus 1.5 – 2.3 × 1.5 – 2.1 mm, pale yellow-green, fleshy, with 6 thickened longitudinal ribs, opaque or almost so in dried material; staminodia to c. 0.3 mm long, staminiform, in a ring around style base; styles 3, erect, 1.1 – 1.8 mm long, fused to form a column, free and divergent at apices, stigmas 3, ovate in outline and deeply bifid, styles green, stigmatic surfaces pale green-yellow
Morphology Reproductive morphology Fruits
Capsule 14 – 24 × 10 – 15 mm, oblong-elliptic to oblong-obovate in outline, rarely elliptic, lobes thickly chartaceous, rigid, base cuneate to rounded, apex rounded to truncate, ascending at c. 45 – 30° to axis at dehiscence on a 1.1 – 2.8 mm long, weakly clavate in outline, 3-angled pedicel, white to pale green when immature, drying pale tan with darker brown speckling like capsule, torus and tepals persistent in fruit until dehiscence in some cases, marginal strip present, opening from apex to expose seed
Morphology Reproductive morphology Inflorescences
Inflorescences simple, pendent, axes ridged and longitudinally winged, wing broadest at nodes Male inflorescences 1 (– 2) per axil, racemose, lax to dense, with axis from (0.5 –)1.2 to more than 50 cm long (including 0.3 – 2.2 cm long peduncle), 0.5 – 1 mm wide including wing, pale green; flowers in cymules of 2 – 4 per node or sometimes solitary, especially towards inflorescence apex (but always some cymules present at base), nodes 2 – 20 mm apart, primary branch of cymule not more than 0.3 mm long, so cymule appears fasciculate; cymule bract 1.2 – 2.3 mm long, ovate, acuminate, membranous; female inflorescences 1 per axil, to at least 20 cm long, including peduncle to 3.5 cm long, spicate, axes 0.9 – 1.1 mm wide including wing, pale green
Morphology Reproductive morphology Seeds
Seeds winged at base only and therefore concealed until release, 6.5 – 7.0 × 4.0 – 5.0 mm excluding wing, flattened-reniform, dark brown, wing 6.5 – 9.0 × 4.0 – 5.0 mm, oblong to oblong-elliptic, apex acute to obtuse, membranous, golden-brown.
Morphology Stem
Stems below ground white with roots at nodes Stems above ground left-twining, to 7 mm in diam., terete or with low, prickly basal ridges when fresh, but often longitudinally ridged when dry, unarmed, green, sometimes with purple or brown markings
Note
The specimens known to Perrier and collected prior to 1910 were Perrier 822, 822bis and 8202, Perville 632 and Baron 5364, based on those cited in Perrier (1928). These specimens must therefore be syntypes. Perrier 8202 is therefore selected as the lectotype, because it is the most representative collection and because it is the only collection in the type cover at P, perhaps at Perrier’s suggestion. The male sheet with the most material at P should be the lectotype, with the other three sheets being isolectotypes. Dioscorea maciba can often be identified in sterile condition by the horseshoe-shaped basal sinus, and sometimes by the presence of an irregular white central blotch in juvenile leaves. To be certain, however, the presence of male flowers in cymules at least towards inflorescence axis bases needs to be observed. The entire leaf margins and lower elevational range of D. maciba make it unlikely to be confused with D. acuminata, although the distribution of the latter approaches that of the former at Midongy.
Type
Madagascar, Majunga [Mahajanga] Prefecture, Haut Bemarivo (Boina), ♂ fl. March 1907, Perrier 8202 (lectotype P!, selected here; isolectotypes K!, P!). Remaining syntypes from protologue: see notes below.
Vegetative Multiplication Tubers
Tubers annually replaced, one per growing season, divergent, usually buried c. 0.6 – 2 m deep, usually c. 40 – 60 × 1 cm at crown and 6 cm at apex, narrowly claviform, sometimes as long as 1 m and weighing up to 10 kg (according to Burkill & Perrier (1950), but we have not seen any exceeding 3 – 4 kg) or as small as c. 2.5 cm × 2 mm at crown and 6 mm at apex (when young), periderm light brown to red-brown, parenchyma white, mucilaginous, crown not clearly differentiated from tuber apex but bearing thicker roots, chartaceous cataphylls present around point of stem insertion
Vernacular
Ovy (Sakalava, throughout Menabe), Maciba, Malita (Sakalava), Kasy (Sakalava, Mahabo).

[KBu]
Use
Tuber edible (cooked); one of the most favoured yams of Western Madagascar. Sold cooked on the roadsides as a snack. The tuber tends to be hard to dig, because it can be deeply buried (more than 2 m) and thus is sometimes known as “the yam that makes you desperate”.

Native to:

Madagascar

Dioscorea maciba Jum. & H.Perrier appears in other Kew resources:

Date Reference Identified As Barcode Type Status
Jun 10, 2013 Randriamboavonjy, T. [RTI 1140], Madagascar K000953443
Jun 10, 2013 Randriamboavonjy, T. [RTI 1141], Madagascar K000953444
Jun 10, 2013 andriamboavonjy, T. [RTI 1157], Madagascar K000953456
Jan 1, 2012 De Block et al. [2206], Madagascar K000524397
Jan 1, 2012 De Block et al. [2224], Madagascar K000524399
Jun 1, 2004 Maurin, O. [80], Madagascar 76239.000
Wilkin, P. [964], Madagascar K000383734
Wilkin, P. [1139], Madagascar K000383755
Wilkin, P. [1140], Madagascar K000383760
Perrier de la Bâthie, H. [s.n.], Madagascar K000383846
Andriamahay, M. [2244], Madagascar K000728355
Maurin, O. [80], Madagascar K001148359
Rajaonah, M.T. [MT 065], Madagascar K001171762
Baron, R. [5364], Madagascar K000383851
Caddick, L.R. [319], Madagascar K000383733
Dequaire, J. [27025], Madagascar K000383853
Wilkin, P. [1149], Madagascar K000523585
Bardot-Vaucoulon, M. [1805], Madagascar K001171811
Caddick, L.R. [318], Madagascar K000383744
Wilkin, P. [1100], Madagascar K000383750
Wilkin, P. [1112], Madagascar K000383753
Block, De [583], Madagascar K000523586
Cours, G. [5088], Madagascar K000383854
Perrier de la Bâthie, H. [8202], Madagascar K000383845
Wilkin, P. [1139], Madagascar K000383756
Wilkin, P. [1113], Madagascar K000383758
Humbert, H. [7084], Madagascar K000383844
Baron, R. [4801], Madagascar K000383850
Wilkin, P. [M970], Madagascar K000383739
Greve [135], Madagascar K000383843
Wilkin, P. [1101], Madagascar K000383751
Wilkin, P. [1100], Madagascar K000383746
Wilkin, P. [1140], Madagascar K000383761
Wilkin, P. [964], Madagascar K000383736
Leandri, J. [2131], Madagascar K000383852
Caddick, L.R. [318], Madagascar K000383745
Hanitrarivo, R.M. [HRM 353HRM 353], Madagascar K001171812
Caddick, L.R. [319], Madagascar K000383732
Wilkin, P. [1112], Madagascar K000383754
Caddick, L.R. [328], Madagascar K000383742
Wilkin, P. [1148], Madagascar K000383763
Humbert, H. [14352], Madagascar K000383847
Bernier [264], Madagascar K000383839
Wilkin, P. [971], Madagascar K000383740
Wilkin, P. [971], Madagascar K000383737
Wilkin, P. [1113], Madagascar K000383759
Perrier de la Bâthie, H. [822], Madagascar K000383841
Greve [135], Madagascar K000383849
Wilkin, P. [1149], Madagascar K000523584
Wilkin, P. [1149], Madagascar K000523582
Perrier de la Bâthie, H. [8202], Madagascar K000383848
Wilkin, P. [1100], Madagascar K000383747
Andriamahay, M. [2037], Madagascar K000728356
Wilkin, P. [1113], Madagascar K000383757
Caddick, L.R. [328], Madagascar K000383741
Wilkin, P. [971], Madagascar K000383738
Wilkin, P. [1101], Madagascar K000383752
Wilkin, P. [1100], Madagascar K000383748
Perrier de la Bâthie, H. [822], Madagascar K000383842 Unknown type material
Wilkin, P. [1149], Madagascar K000523583
Wilkin, P. [964], Madagascar K000383735
Wilkin, P. [1148], Madagascar K000383762
Wilkin, P. [1100], Madagascar K000383749
Caddick, L.R. [327], Madagascar K000383743
Perrier de la Bâthie, H. [822], Madagascar K000383840
Hladik, A. [6790], Madagascar K000523575

First published in Compt. Rend. Hebd. Séances Acad. Sci. 149: 486 (1909)

Accepted by

  • Wilkin, P., Andrianantenaina, W.P., Jeannoda, V. & Hladik, A. (2008 publ. 2009). The species of Dioscorea L. (Dioscoreaceae) from Madagascar with campanulate tori, including a new species from Eastern Madagascar Kew Bulletin 63: 583-600.

Not accepted by

  • Govaerts, R. (2000). World Checklist of Seed Plants Database in ACCESS D: 1-30141. [Cited as Dioscorea sansibarensis.]
  • Govaerts, R., Wilkin, P. & Saunders, R.M.K. (2007). World Checklist of Dioscoreales. Yams and their allies: 1-65. The Board of Trustees of the Royal Botanic Gardens, Kew. [Cited as Dioscorea sansibarensis.]

Literature

Kew Backbone Distributions

  • Wilkin, P., Andrianantenaina, W.P., Jeannoda, V. & Hladik, A. (2008 publ. 2009). The species of Dioscorea L. (Dioscoreaceae) from Madagascar with campanulate tori, including a new species from Eastern Madagascar Kew Bulletin 63: 583-600.

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 2021. 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 2021. 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