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  1. Family: Acanthaceae Juss.
    1. Ruellia Plum. ex L.

      1. This genus is accepted, and its native range is Tropical & Subtropical to N. America.


    Acanthaceae (part 2), Kaj Vollesen. Flora of Tropical East Africa. 2008

    Erect shrubby perennial herb, 1 m tall; young stems sparsely puberulous and with scattered glands in two bands below nodes Perennial or shrubby herbs or shrubs; cystoliths conspicuous
    Flowers solitary in leaf axils towards apex of stem; pedicels 0–1 mm long; bracteoles narrowly ovate, up to 2.2 × 0.5 cm, decurrent into a petiole which is longer than the lamina Flowers solitary or paired in leaf axils or in variously branched cymes or panicles; bracts persistent, leaf-like; bracteoles persistent (rarely caducous), usually large and leafy
    Calyx 16–20 mm long, divided to 1–2 mm from base; puberulous with glandular and non-glandular hairs; lobes linear Calyx 5-lobed, deeply divided into 5 subequal lobes or 2–3 lobes fused higher up; lobes usually with distinct dorsal keel, dorsal usually slightly longer than the rest
    Corolla open during the day, blue (? mauve); tube ± 5 cm long of which the basal cylindric part ± 3.5 cm and the throat ± 1.5 cm long; lobes ± 1 × 1 cm, broadly ovate with rounded apex Corolla hairy on the outside, contorted in bud, subactinomorphic; basal cylindric part of tube short to long, throat short to long, usually much widened upwards; lobes 5, subequal, spreading
    Stamens included in throat, slightly didynamous; filaments fused for ± 3 mm at base, free parts ± 6 and 8 mm long, longer with scattered spreading hairs near base; anthers ± 5.5 mm long Stamens 4, subequal to didynamous, inserted near base of throat, exserted or included in throat; free part of filaments fused at base, below insertion forming two ridges running to base of tube; anthers 2-thecous, thecae oblong, rounded at base, without spurs, connective with small curved appendage at apex
    Ovary not seen. Ovary with 3 to many ovules per locule.
    Lowland semi-evergreen forest; ± 175 m
    Known only from this collection. Superficially close to R. amabilis from which it differs in the cuneate leaf-base, broader bracteoles, shorter corolla tube, sessile flowers and blue corolla. These two last characters indicate that its real affinity is possibly more with the R. patula-group. From the species in this group it differs in the large anthers, large capsule and large seeds. The native East African species all belong to Subgen. Dipteracanthus (Nees) C.B.Clarke which is characterised by having a clavate capsule with sterile basal part.
    Leaves opposite, entire to crenate Leaves with petiole 1–3.5 cm long, densely puberulous; lamina ovate, largest 9 × 4.2 cm, apex gradually narrowed into an elongated acute tip, base cuneate, unequal-sided, sparsely puberulous and with scattered glands
    Style filiform, hairy throughout or glabrous towards apex.
    Stigma with dorsal lobe reduced to a small tooth (rarely well developed), ventral lobe large, flattened to spoon-shaped with wavy margin Ventral stigma lobe ± 3 mm long
    Capsule cylindric to clavate, valves eventually splitting lengthwise from bottom up along dorsal suture, with 4 to over 20 seeds; retinaculae strongly hooked Capsule strongly clavate, with scattered capitate glands in upper 1/4, ± 27 mm long, 8-seeded
    Seed discoid, faces glabrous or with discoid hairs, rim strongly raised and with dense hygroscopic hairs Seed orbicular, dark brown, ± 6 × 5.5 mm.
    Range: Not known elsewhere Flora districts: T6 Range: About 250 species widely distributed in all tropical regions, most numerous in South America.



    Native to:

    Alabama, Aldabra, Andaman Is., Angola, Argentina Northeast, Argentina Northwest, Arizona, Aruba, Bahamas, Bangladesh, Belize, Benin, Bolivia, Borneo, Botswana, Brazil North, Brazil Northeast, Brazil South, Brazil Southeast, Brazil West-Central, Burkina, Burundi, Cabinda, Cameroon, Cape Provinces, Caprivi Strip, Cayman Is., Central African Repu, Chad, China South-Central, China Southeast, Christmas I., Colombia, Congo, Costa Rica, Cuba, Delaware, District of Columbia, Djibouti, Dominican Republic, Ecuador, El Salvador, Equatorial Guinea, Eritrea, Ethiopia, Florida, Free State, French Guiana, Gabon, Galápagos, Georgia, Ghana, Guatemala, Guinea, Gulf of Guinea Is., Guyana, Hainan, Haiti, Honduras, Illinois, India, Indiana, Ivory Coast, Jamaica, Jawa, Kentucky, Kenya, KwaZulu-Natal, Laccadive Is., Laos, Leeward Is., Liberia, Louisiana, Madagascar, Malawi, Malaya, Mali, Mauritania, Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Northwest, Mexico Southeast, Mexico Southwest, Michigan, Mississippi, Missouri, Mozambique, Myanmar, Namibia, Nebraska, Netherlands Antilles, New Caledonia, New Guinea, New Jersey, New Mexico, New South Wales, Nicaragua, Niger, Nigeria, Northern Provinces, Northern Territory, Oklahoma, Oman, Pakistan, Panamá, Paraguay, Pennsylvania, Peru, Philippines, Puerto Rico, Queensland, Rwanda, Samoa, Saudi Arabia, Senegal, Sierra Leone, Socotra, Somalia, South Australia, South Carolina, Southwest Caribbean, Sri Lanka, Sudan, Sulawesi, Suriname, Swaziland, Taiwan, Tanzania, Tennessee, Texas, Thailand, Togo, Trinidad-Tobago, Turks-Caicos Is., Uganda, Uruguay, Vanuatu, Venezuela, Venezuelan Antilles, Vietnam, Virginia, Wallis-Futuna Is., West Virginia, Western Australia, Windward Is., Yemen, Zambia, Zaïre, Zimbabwe

    Introduced into:

    Arkansas, Assam, Bermuda, Cambodia, Cook Is., Fiji, Gambia, Hawaii, Lesser Sunda Is., Marianas, Mauritius, Nauru, New York, Nicobar Is., Réunion, Seychelles, South China Sea, Tokelau-Manihiki

    Accepted Species


    Other Data

    Ruellia Plum. ex L. appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    Jan 1, 1990 Botteri, M. [492], Mexico K000064386
    Harley, R.M. [16850], Brazil K001032635
    Harley, R.M. [15382], Brazil K001032636
    Harley, R.M. [21371], Brazil K001032637
    Harley, R.M. [21371], Brazil K001032638
    Harley, R.M. [16850], Brazil K001032645
    Harley, R.M. [22458], Brazil K001032715
    Harley, R.M. [22458], Brazil K001032716
    Harley, R.M. [24308], Brazil K001032725
    Harley, R.M. [16758], Brazil K001032743
    Harley, R.M. [s.n.], Brazil K001032747
    Harley, R.M. [27722], Brazil K001046159
    Williams, R.O., Tanzania 2935.000
    Trail, J.W.H. [644], Brazil K001032720
    Harley, R. [6004], Brazil K001032721
    Taylor, N.P. [422], Mexico K000064377
    Beentje, H.J. [4593], Madagascar 60561.000
    Rico, L. [2013], Mexico K000265995
    Gilbert [57], Paraguay K001032689
    Santos, T.S. [1955], Brazil K001032730
    Giulietti, A.M. [1202], Brazil K001032728
    Sakuragui, C.M. [CFCR 15173], Brazil K001046160
    Coradin, L. [6022], Brazil K001032746
    Lucena, M.F.A. [45], Brazil K001032647
    Oliveira, M. [63], Brazil K001032640
    Gomes, A.P.S. [55], Brazil K001032646
    Lira, S.S. [20], Brazil K001032723
    Heringer, E.P. [16011], Brazil K001046154
    Andrade, K. [205], Brazil K001032644
    Preston, T.A. [s.n.], Brazil K001032692
    Villarouco, F.M.O. [124], Brazil K001032722
    Bolland, G. [13], Brazil K001032738
    Fonseca, M.L. [1049], Brazil K001032693
    Brooks, R.R. [639], Brazil K001046161
    Krukoff, B.A. [6022], Brazil K001032727
    Krukoff, B.A. [4971], Brazil K001046152
    Krukoff, B.A. [4971], Brazil K001046153
    Krukoff, B.A. [4708], Brazil K001046158
    Bourgeau, M. [2903], Mexico K000064180
    Bourgeau, M. [2859], Mexico K000064385
    Mori, S. [10257], Brazil K001046162
    Teixeira, L.O.A. [319], Brazil K001032745
    Weir, J. [s.n.], Brazil K001032717
    Sellow [788], Brazil K001032690
    Sellow [s.n.], Brazil K001032744
    Tschá, M.C. [302], Brazil K001032641
    Tschá, M.C. [313], Brazil K001032642
    Figueirêdo, L. [215], Brazil K001032724
    Melo, M.R.C.S. [215], Brazil K001032643
    Forzza, R.C. [4058], Brazil K001032634
    Félix, L.P. [1640], Brazil K001032734
    Saint-Hilaire, A. [494], Brazil K001032732
    Saint-Hilaire, A. [304], Brazil K001032733
    Prance, G.T. [16778], Brazil K001032691
    Prance, G.T. [58653], Brazil K001032719
    Prance, G.T. [14100], Brazil K001032735
    Prance, G.T. [12304], Brazil K001032736
    Prance, G.T. [14583], Brazil K001032740
    Strudwick, J.J. [3044], Brazil K001032741
    Mexia, Y. [5352], Brazil K001032742
    Lemos, J.R. [242], Brazil K001032729
    Burchell [8928], Brazil K001032639
    Burchell [7417], Brazil K001032726
    Burchell [8064], Brazil K001032739
    Burchell [5951], Brazil K001046155
    Burchell [5951], Brazil K001046156
    Burchell [8941-2], Brazil K001046157
    Glaziou [17173], Brazil K001032718
    Glaziou [15296], Brazil K001032731
    Glaziou [18397], Brazil K001032737


    First published in Sp. Pl.: 634 (1753)

    Accepted by

    • Tripp, E.A. & McDade, L.A. (2012). New synonymies for Ruellia (Acanthaceae) of Costa Rica and notes on other neotropical species Brittonia 64: 305-317. New York Botanical Garden.


    Flora of West Tropical Africa

    • —F.T.A. 5: 44.

    Flora of Tropical East Africa

    • F.T.A. 5: 44 (1899)
    • DC., Prodr. 11: 143 (1847)
    • Sp. Pl.: 634 (1753)
    • G.P. 2: 1077 (1876)


    Flora of Tropical East Africa
    Flora of Tropical East Africa

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