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  1. Family: Acanthaceae Juss.
    1. Genus: Barleria L.
      1. Barleria microcalyx I.Darbysh.

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


    Darbyshire, I., Phillipson, P.B. & Rakotonasolo, F. 2014. Additions to the genus Barleria in Madagascar. Kew Bulletin 69: 9513. DOI

    Type: Madagascar, Antsiranana, Daraina, forêtd’Antsaharaingy, Ranirison PR 669 (holotype K!; isotypes CAS, Daraina, G, TEF).
    Perennial herb or subshrub, 60 – 80 cm tall; young stems drying blackish-brown, subangular, patently glandular-pilose, multicellular hairs appearing deflated in dry state, also with minute white retrorse and antrorse eglandular hairs on two opposite sides, these becoming very dense and conspicuous in two lines on short uppermost internodes and along internodal line, appearing woolly; mature stems softly woody with pale brown bark
    Leaves chartaceous, ovate or trullate, lower cauline leaves 6.5 – 11 × 3.2 – 5.7 cm, base broadly cuneate or somewhat attenuate, margin entire or obscurely repand, apex acute to obtuse or subattenuate, apiculate; surfaces glabrous except for short glandular hairs towards midrib beneath and longer glandular hairs along margin towards base, lower surface also with numerous sessile glands; lateral veins 4 – 5 pairs; petiole 24 – 52 mm long, patently glandular-pubescent and with dense short woolly hairs in proximal portion of adaxial groove
    Inflorescences of sessile single-flowered cymes crowded in upper axils between short internodes to form a terminal fascicle; bracts foliaceous but reduced and subsessile, ovate or ovate-elliptic to narrowly so, typically 25 − 40 × 7 − 16 mm, margin glandular-pubescent; bracteoles like bracts but oblong-elliptic to narrowly oblong, 16.5 – 25.5 × 4.5 – 8 mm
    Calyx hidden within bracteoles, brown in dry state, lobes rather membranous, base thickened; anterior lobe triangular, 4.2 – 4.6 × 2 mm, margin entire, apex subattenuate into a short flexuose point, surfaces glabrous or with minute appressed hairs along margin, venation parallel with central pair of veins most prominent; posterior lobe like anterior lobe but 5 – 5.5 mm long, single central vein most prominent; lateral lobes lanceolate, 4.5 – 5.5 × 1.5 mm, sometimes with few short glandular hairs
    Corolla pale violet to mauve with a white base to tube, 48 − 63 mm long, sparsely glandular-pubescent externally mainly on lateral lobes; tube 24.5 – 29 mm long, subcylindrical but gradually and narrowly expanded upwards, c- 2.5 – 3 mm in diam- at base, to 5.5 – 6.5 mm at mouth; limb in “4+1” arrangement; abaxial lobe offset from remaining lobes by 4.5 − 8 mm, broadly elliptic, 18.5 – 30 × 12.5 – 16 mm, apex rounded; lateral lobes oblong-elliptic, 17 – 26.5 × 10 – 16 mm, apex rounded and minutely notched; adaxial lobes like lateral lobes but 16.5 – 24 × 8.5 – 11.5 mm
    Stamens attached 7 – 9.5 mm from base of corolla tube; filaments 27.5 – 32.5 mm long, shortly hairy at base; anthers exserted, 4.7 – 5.5 mm long; staminodes absent
    Ovary glandular-puberulous distally; style glabrous; stigma violet, linear, 4 – 4.5 mm long
    Capsule 15 – 16 mm long including sterile beak 6 – 7 mm long, beak glandular-pubescent; septum with a shallow membranous portion; immature seeds 5.5 mm long, clothed in matted buff-coloured hygroscopic hairs
    Differs from all other species in Barleria sect. Somalia in having the combination of a tiny calyx relative to the corolla (length ratio 0.08 – 0.1 : 1), the absence of staminodes and the short white woolly indumentum in two opposite lines on the uppermost internodes, along the interpetiolar line and within the petiolar groove. The two-seeded, prominently beaked capsule with a membranous portion to the septum, the linear stigma and the absence of spines together place Barleriamicrocalyx in Barleria sect. Somalia (Balkwill & Balkwill1997; Darbyshire2009). Six of the species recorded by Benoist (1967) belong to that section: B. insolita Benoist, B. laeta Benoist, B. longipes Benoist (including B. puberula Benoist which is probably a distinct species), B. pulchella Benoist, B. separata Benoist and B. seyrigii Benoist. In Benoist’s key, B. microcalyx would be identified as B. laeta, the only other species with a hairy ovary and capsule. Indeed, B. microcalyx superficially resembles that species in, for example, leaf shape and corolla size. However, the two are easily separated by a number of characters listed in Table 2. Particularly striking is the minute calyx of the new species which is hidden within the leafy bracteoles, whereas in B. laeta the large, leafy calyces are clearly exposed beyond the bracteoles.
    Northern Madagascar.
    Recorded from lowland dry forest on slopes and ridges, with a sparse herbaceous understorey; 60 – 180 m alt.
    This species is recorded from a very restricted range (EOO 257 km2, AOO 12 km2, 3 locations). Habitat loss and degradation in the Daraina region through artisanal gold mining and tree felling pose inferred threats to these locations, although the area is currently under 'temporary protection' within the proposed new protected area: Loky-Manambato. It is therefore considered Endangered [EN B1ab (i, ii, iii, iv) + B2ab (i, ii, iii, iv)].



    Native to:


    Other Data

    Barleria microcalyx I.Darbysh. appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    Ranirison, P. [669], Madagascar K001089044 holotype


    First published in Kew Bull. 69(2)-9513: 7 (2014)


    Kew Bulletin

    • IUCN (2013). Guidelines for using the IUCN Red List Categories and Criteria. Version 10.1. Available at Accessed 13 December 2013.
    • Darbyshire, I. (2009). A reassessment of the status of Barleria sect. Cavirostrata (Acanthaceae) in tropical Africa, with a new species, B. richardsiae, described from the Tanzania-Zambia border region. Kew Bull. 63: 601 – 611.CrossRefGoogle Scholar
    • McDade, L. A., Daniel, T. F. & Kiel, C. A. (2008). Toward a comprehensive understanding of phylogentic relationships among lineages of Acanthaceaes.l. (Lamiales). Amer. J. Bot. 95: 1136 – 1152.CrossRefGoogle Scholar
    • IUCN (2001). IUCN Red List Categories and Criteria. Version 3.1. IUCN Species Survival Commission, IUCN, Gland and Cambridge.Google Scholar
    • Balkwill, M.-J. & Balkwill, K. (1998). A preliminary analysis of distribution patterns in a large, pantropical genus, Barleria L. (Acanthaceae). J. Biogeogr. 25: 95 – 110.CrossRefGoogle Scholar
    • Balkwill, M.-J. & Balkwill, K. (1997). Delimitation and infra-generic classification of Barleria (Acanthaceae). Kew Bull. 52: 535 − 573.CrossRefGoogle Scholar
    • Benoist, R. (1967). Acanthacées. Tome I. In: H. Humbert (ed.), Flore de Madagascar et des Comores. Museum National d’HistoireNaturelle, Laboratoire de Phanérogamie, Paris.Google Scholar


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