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This species is accepted, and its native range is Guinea to Sierra Leone.


Goyder, D.J. (2008). Xysmalobium samoritourei (Apocynaceae: Asclepiadoideae), a new species from the Guinea Highlands of West Africa. Kew Bulletin 63: 473.

VU B2a,b (iii). The Guinea populations were discovered during a botanical survey of the Simandou Range prior to proposed extraction of iron ore from some parts of the ridge. In addition to the specimens cited above, the following sight record should be noted: Simandou range northern part, near Mont Gbein or Mount Captain Hook, 30 March 2008 (sight record only (van der Burgt pers. comm.)). The three known populations were found outside the areas selected for mining activity. In Sierra Leone, the three localities are widely scattered, and as the plant is inconspicuous it may have been overlooked elsewhere. Since six sites are known, with an estimated area of occupancy of less than 24 km2, and a decline in habitat quality is expected due to mining activity, a conservation assessment of Vulnerable, VU B2a,b(iii), is proposed using IUCN (2001) criteria.
Known from five collections and one sight record from the Guinea Highlands of West Africa. So far, Xysmalobium samoritourei appears restricted to Guinea (Conakry) and Sierra Leone — Adam (1975) did not record it from the nearby Liberian massif of Mt Nimba.
Montane grassland; alt. 1100 – 1600 m.
Morphology General Habit
Erect perennial herb with annual stems arising from a vertical carrot-shaped tuber 1 – 4 cm below the soil surface; latex white; stems single and unbranched, 15 – 35 cm tall, minutely pubescent with short curled hairs in two lines at least near the upper nodes
Morphology Leaves
Leaves sessile or subsessile; lamina 6 – 10 × 0.2 – 0.4 cm, linear, acute, glabrous, subcarnose with prominent midrib and marginal veins
Morphology Reproductive morphology Flowers Androecium Stamens Anthers
Anther appendages membranous, c. 0.7 × 0.7 mm, broadly ovate, acute, inflexed over apex of stylar head Anther wings c. 1 mm long, somewhat flared towards the base, truncate basally and lacking tails or basal appendages
Morphology Reproductive morphology Flowers Calyx
Calyx lobes c. 1 mm long, triangular, acute
Morphology Reproductive morphology Flowers Corolla
Corolla lobed ± to the base, cream or yellow-green tinged with pink distally particularly on the abaxial surface; lobes strongly reflexed, 3 – 4 × 1 – 1.5 mm, oblong, the tips rounded to subacute, glabrous on both faces
Morphology Reproductive morphology Flowers Gynoecium Style
Apex of stylar head ± level with top of anthers, pentagonal-Follicles (immature) solitary, erect, 7.5 × 0.5 cm, narrowly fusiform, smooth, subglabrous.
Morphology Reproductive morphology Flowers Gynostegium
Gynostegial stipe 1 mm long Gynostegial corona yellow, with 5 fleshy staminal lobes linked by minute interstaminal teeth at the base; staminal lobes c. 0.7 mm wide at the base, c. 0.5 mm thick, forming a fleshy vesicle at the base of the staminal column but on drying the lobe resembles a narrow downward-pointing tongue
Morphology Reproductive morphology Flowers Pollinarium
Corpusculum 0.3 × 0.1 – 0.15 mm, black, ovoid to subcylindrical; translator arms 0.3 – 0.4 mm long, flattened, geniculate; pollinia 0.8 – 0.9 × 0.3 mm flattened, subelliptical or oblong
Morphology Reproductive morphology Inflorescences
Inflorescences solitary, terminal, sessile or shortly pedunculate, umbelliform, with 25 – 50 flowers open simultaneously; peduncles to 3 mm long, pubescent; pedicels 10 – 15 mm long, pubescent
The new species commemorates Samori Touré who was born in the Guinea Highlands and became leader of a 19th Century resitance movement opposing French colonial expansion in West Africa. While Xysmalobium samoritourei and X. holubii are both pyrophytic herbs of fire-prone grasslands, the new species is restricted to apparently well-drained montane grassland, and X. holubii is a species of seasonally waterlogged ‘dambo’ grassland. Morphologically the two species appear close, but X. samoritourei can readily be distinguished from X. holubii on the basis of its solitary terminal inflorescence and the form of the anther wings which lack the basal extensions found in X. holubii, and are somewhat flared from the column basally — anther wing margins in the latter species are parallel to each other. The two species are geographically disjunct, with X. samoritourei restricted to the Guinea Highlands of West Africa, while X. holubii occurs much further south in Angola, Congo (Kinshasa), Zambia, Malawi and Zimbabwe.
Apparently flowering early in the rainy season.
Guinea (Conakry), Simandou Range, 0.5 km N of Dabatini, on ridge from Oueleba to Dabatini, 27 March 2008, Couch, van der Burgt, Haba & Haba 556 (holotypus K; isotypi NHGC, WAG).

Native to:

Guinea, Sierra Leone

Xysmalobium samoritourei Goyder appears in other Kew resources:

Date Reference Identified As Barcode Type Status
Jan 1, 2008 Gledhill, M. [SL 1828], Sierra Leone 58625.000
Jan 1, 2008 Jordan [1060], Sierra Leone 58635.000
Jan 1, 2008 Jaeger [9467], Sierra Leone 58636.000

First published in Kew Bull. 63: 473 (2008 publ. 2009)

Accepted by

  • Govaerts, R., Nic Lughadha, E., Black, N., Turner, R. & Paton, A. (2021). The World Checklist of Vascular Plants, a continuously updated resource for exploring global plant diversity. Scientific Data 8: 215.


Kew Bulletin

  • Adam, J.-G. (1975). Asclépiadacées. In: J.-G. Adam, Flore descriptive des Monts Nimba (3e partie). Mém. Mus. Natl. Hist. Nat., sér. B, Bot. 24: 969 – 977, 1178 – 1190.
  • Bullock, A. A. (1963). Asclepiadaceae. In: F. N. Hepper (ed.), Flora of West Tropical Africa ed. 2, 2: 85 – 103. Crown Agents for Overseas Governments and Administrations, London.
  • Goyder, D. J. (2009). A synopsis of Asclepias (Apocynaceae: Asclepiadoideae) in tropical Africa. Kew Bull. 64: 369.
  • Goyder, D. J. , Nicholas, A. & Liede-Schumann, S. (2007). Phylogenetic relationships in subtribe Asclepiadinae (Apocynaceae: Asclepiadoideae). Ann. Missouri Bot. Gard. 94: 423 – 434.
  • IUCN (2001). IUCN Red List categories and criteria, version 3.1. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, UK.
  • Jaeger, P. & Adam, J.-G. (1981). Asclépiadacées. In: P. Jaeger & J.-G. Adam, Recensement des végétaux vasculaires des Monts Loma (Sierra Leone) et des pays de piedmont. Deuxième partie. Ebénacées – Ptéridophytes Filicales. Boissiera 33: 35 – 39.
  • Liede-Schumann, S., Rapini, A., Goyder, D. J. & Chase, M. (2005). Phylogenetics of the New World subtribes of Asclepiadeae (Apocynaceae – Asclepiadoideae): Metastelmatinae, Oxypetalinae and Gonolobinae. Syst. Bot. 30: 184 – 195
  • Rapini, A., Chase, M. W., Goyder, D. J. & Griffiths, J. (2003). Asclepiadeae classification: evaluating the phylogenetic relationships of New World Asclepiadoideae (Apocynaceae). Taxon 52: 33 – 50

Herbarium Catalogue Specimens

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© Copyright 2017 World Checklist of Selected Plant Families.

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Kew Names and Taxonomic Backbone
The International Plant Names Index and World Checklist of Selected Plant Families 2021. Published on the Internet at and
© Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families.