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  1. Family: Aspleniaceae Newman
    1. Genus: Asplenium L.
      1. Asplenium inaequilaterale Willd.

        This species is accepted, and its native range is Tropics & Subtropics.


    Aspleniaceae, Henk Beentje. Flora of Tropical East Africa. 2008

    Type: Réunion, Bory de St Vincent in herb. Willdenow 19896 (B-W, holo.)
    Terrestrial or on rocks, rarely a low epiphyte.
    Rhizome erect, 4–8 mm diameter, with dark brown entire clathrate lanceolate attenuate rhizome scales 2–3 × 0.6 mm, the margin mid-brown.
    Frond tufted, erect, not proliferous.
    Stipe pale to dark matt-brown or greenish-brown, 4–19 cm long, sparsely covered at first with minute hair-like scales, rarely with a few stalked glands, glabrous at maturity.
    Leaf lamina
    Lamina narrowly ovate, 12–32 × 4–13 cm, 1-pinnate, with lowest pinnae not markedly reduced; apical segment lobed, crenate, attenuate.
    Pinnae in 8–20 pairs, herbaceous, narrowly to very narrowly oblong or roughly lanceolate, sometimes falcate, 1.5–6.3 × 0.7–1.2 cm, unequally cuneate at the base, acroscopic lobe well-developed, crenate or doubly crenate, apex obtuse to attenuate, shortly petiolate; glabrous on both surfaces.
    Rachis pale brown, narrowly winged on the upper part of the lamina.
    Sori 3–16, linear (to oblong in small fronds), set at an angle of 30–45° to the costa, 2–7 mm long.
    Indusium linear to oblong, membranous, entire, 0.5–1 mm wide.
    Fig. 6: 5–6, p. 37.
    Moist forest, on rocks by streams or on forest floor; 700–2100 m
    Widespread; least concern (LC)
    A series of specimens from U 1, Mt Debasien, collected by H.D. van Someren (602, 603, 613, 614, 627) all key to this taxon but have a slightly different look to the pinnae, with 2-toothed sub-lobes. Richards 14239 from T 7 is similar. A specimen from Tanzania, Tanga District: Mtai Forest Reserve, Lovett & Hamilton 891! has a different look and feel from A. inaequilaterale, to which it seems closest. It might otherwise be close to A. christii from which it differs in obtuse pinna apices. It is a low epiphyte with scales dark brown, clathrate, narrowly ovate to triangular, to 1.2 × 0.5 mm. Lamina oblong, 12 × 3–4.5 cm. Pinnae in 6 pairs, asymmetrically ovate, the largest 1.8–2.3 × 1.3–1.5 cm, obtuse, margin crenualate, glabous or nearly so; terminal pinna similar to laterals. Sori 9–13 per lobe, reaching neither costa nor margin, on the branched veins and 3–5 mm long; involucre whitish, membranous, entire, to 0.4 mm wide. Epiphytic on base of tree trunks in ‘elfin’ forest, at an altitude of 1045 m. The mention of Asplenium pulchellum Hiern in P.O.A. C is probably based on this taxon. Faden felt several specimens from Meru, which he named A. suppositum, differed in the smaller, more finely toothed and more numerous pinnae, which give this plant a look different from A. inaequilaterale and he considered them distinct; they grow side by side with A. inaequilaterale in the lower Imenti forest near Meru. The type of A. suppositum, from Angola, is certainly A. inaequilaterale. This taxon differs from A. unilaterale chiefly in its erect rhizome and tufted fronds. It is also close to A. macrophlebium which is usually proliferous, and has the veins mostly unbranched.
    Range: Tropical Africa and south to South Africa, Comoro Is., Réunion Flora districts: U1 U2 U3 U4 K3 K4 K5 K7 T1 T2 T3 T4 T6 T7 T8



    Native to:

    Angola, Assam, Bolivia, Brazil Northeast, Brazil South, Brazil Southeast, Brazil West-Central, Burundi, Cameroon, Cape Provinces, Central African Repu, Comoros, Ethiopia, Free State, Gabon, Ghana, Guinea, Gulf of Guinea Is., India, Kenya, KwaZulu-Natal, Liberia, Madagascar, Malawi, Mozambique, Northern Provinces, Paraguay, Réunion, Sierra Leone, Sri Lanka, Sudan, Swaziland, Tanzania, Thailand, Togo, Uganda, Uruguay, Zambia, Zaïre, Zimbabwe


    Other Data

    Asplenium inaequilaterale Willd. appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    Jan 1, 1998 Thomas, D.W. [9500], Cameroon K000381469
    Drège [50], South Africa K000423971 isolectotype
    Drège [s.n.], South Africa K000423972 isolectotype
    Johnston, Rev. [44], China K000603433
    Jan 1, 1997 Soyaux, H. [234], Angola Asplenium suppositum K000424000


    First published in Sp. Pl., ed. 4, 5: 322 (1810)

    Accepted by

    • Fraser-Jenkins, C.R. & al. (2018). An Annotated Checklist of Indian Pteridophytes 2: 1-573. Dehra Dun : BSMPS.
    • Roskov Y. & al. (eds.) (2018). World Ferns: Checklist of Ferns and Lycophytes of the World Species 2000 & ITIS Catalogue of Life Naturalis, Leiden, the Netherlands.
    • Fraser-Jenkins, C.R. & al. (2017). An Annotated Checklist of Indian Pteridophytes 1: 1-562. Dehra Dun : BSMPS.


    Kew Backbone Distributions

    • Fraser-Jenkins, C.R. & al. (2017). An Annotated Checklist of Indian Pteridophytes 1: 1-562. Dehra Dun : BSMPS.

    Flora of Tropical East Africa

    • U.K.W.F. ed. 2: 29, t. 173 (1994).
    • Fern Gaz. 14, 6: 201 (1993)
    • Johns, Pterid. trop. East Africa checklist: 65 (1991)
    • Burrows, S. Afr. Ferns: 222, map, figs. (1990)
    • Schelpe, F.Z. Pteridophyta: 176, t. 53c (1970)
    • Alston, Ferns W.T.A.: 57 (1959)
    • Mém. Inst. Fr. Afr. Noire, 28: t. 34/4–5 (1953)
    • Sp. Pl. ed. 4, 5: 322 (1810)


    Flora of Tropical East Africa
    Flora of Tropical East Africa

    Herbarium Catalogue Specimens
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    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2020. Published on the Internet at and
    © Copyright 2017 World Checklist of Selected Plant Families.

    Kew Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2020. Published on the Internet at and
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families.