1. Family: Fabaceae Lindl.
    1. Bolusia Benth.

      1. This genus is accepted, and its native range is S. Tropical & S. Africa.

    [FTEA]

    Leguminosae, J. B. Gillett, R. M. Polhill & B. Verdcourt. Flora of Tropical East Africa. 1971

    Habit
    Perennial herbs
    Leaves
    Leaves 1-foliolate or digitately 3-foliolate; stipules leafy, sometimes toothed
    Flowers
    Flowers few in leaf-opposed racemes, occasionally resupinate
    Calyx
    Calyx-lobes subequal in length
    Corolla
    Corolla greenish-yellow to pale pink, sometimes purplish marked; standard shortly clawed, with a very broad blade forming a hood around the keel and bearing 2 small fused ridge-like appendages at the base inside, glabrous or hairy outside; wings auricled; keel produced into a very long narrow beak, which coils spirally through 2·5–3·5 turns
    Stamens
    Vexillary filament free or more commonly joined with the other 9 towards the base of the sheath; anthers dimorphic, 5 long alternating with 5 (perhaps sometimes only 4) much smaller ones
    Pistil
    Ovary usually stipitate, with numerous ovules; style glabrous except for a ring of hairs around the terminal stigma
    Fruits
    Pod inflated, dehiscent
    Seeds
    Seeds oblique-cordiform to nearly horseshoe-shaped, with a deep hilar sinus.
    [LOWO]

    Legumes of the World. Edited by G. Lewis, B. Schrire, B. MacKinder & M. Lock. Royal Botanic Gardens, Kew. (2005)

    Habit
    Perennial herbs
    Ecology
    Seasonally dry tropical to subtropical woodland and xerophytic bushland, shrubland and grassland, usually in rocky or sandy places
    Distribution
    SC and southern Africa
    Note
    Easily recognised by the strange helically coiled keel petals and dentate stipules but the genus seems closely related to Crotalaria; the Madagascan Crotalaria cornu-ammonis R.Vig. appears to be a morphological 'prototype' for the characters found in Bolusia; the generic concept should be tested but an adequate sample of Crotalaria species would need to be included

    The current state of knowledge of the Crotalarieae was reviewed by Van Wyk (1991a) and by Van Wyk & Schutte (1995a). The most conspicuous recent change has been the exclusion of the Argyrolobium group (six genera, i.e. Argyrolobium, Dichilus, Melolobium, Polhillia, Anarthrophyllum and Sellocharis), which belong in tribe Genisteae rather than in Crotalarieae, where they were previously placed (Polhill, 1981q: 399 –402). New insights into relationships within the tribe have come mainly from chemosystematic studies of alkaloids (summarised in Van Wyk & Verdoorn, 1990) and several recent generic monographs (see below).

    The Crotalarieae forms part of a monophyletic clade, the ‘core genistoids’ (Fig. 36) which also includes Genisteae, Podalyrieae, Thermopsideae, Brongniartieae, Euchresteae and Sophoreae sens. strict. (Crisp et al., 2000; Pennington et al., 2000a; Kajita et al., 2001). Crotalarieae appears to be sister to the Genisteae and both are sister to the Podalyrieae (Crisp et al., 2000; Wojciechowski et al., 2004). This clade is in turn sister to the Thermopsideae and Sophoreae sens. strict. (including Euchresteae).

    The Crotalarieae shares with the Podalyrieae the absence of a-pyridone alkaloids such as cytisine and anagyrine that are a typical feature of all other ‘core genistoid’ tribes. Despite a lack of defining characters, the monophyly of the tribe as circumscribed here is well supported by molecular evidence (Crisp et al., 2000; Wink & Mohamed, 2003) and by cladistic analyses of morphological, cytological and chemical characters (Van Wyk & Schutte, 1995a). The latter study suggested an early diversification of the genera with uniform anthers and lupanine-type esters of quinolizidine alkaloids (Pearsonia, Rothia and Robynsiophyton) followed by the poorly known Spartidium and then the so-called ‘Cape group of genera’ (Polhill, 1981q: 399–402), which now includes Lotononis and Crotalaria. Relationships between the seven genera of the ‘Cape group’ remains unresolved despite several recent molecular studies because sampling is still relatively poor. However, a basally branching position in the tribe of the ‘Cape group’, notably Lebeckia and Wiborgia — as considered by Polhill (1976, 1981q) — is now accepted here. The exclusion of the Argyrolobium group, based on morphological and chemical characters, is also strongly supported by DNA sequence data. Due to reticulate and overlapping patterns of character state distribution in the Crotalarieae sens. strict., generic delimitations are intricate and subject to misinterpretation. Several of the large and diverse genera appear to be either monophyletic or paraphyletic depending on the choice of characters. As currently circumscribed the tribe includes 11 genera and c. 1204 species (Fig. 37).

    [FZ]

    Leguminosae, various authors. Flora Zambesiaca 3:7. 2003

    Habit
    Erect to spreading perennial herbs or small suffrutices (one species sometimes annual?).
    Leaves
    Leaves digitately 3-foliolate, rarely 1-foliolate; stipules lanceolate to asymmetrically ovate, more or less truncate at the base, obscurely or markedly dentate, with 1–5 teeth along the outer edge.
    Inflorescences
    Inflorescences leaf-opposed, short, racemose, with 1–5 flowers; bracts and bracteoles linear to lanceolate, persistent.
    Flowers
    Flowers yellow to whitish-cream or flushed with pink or purple.
    Calyx
    Calyx 5-lobed, slightly zygomorphic, the upper pair of lobes slightly broader than the lower 3 lobes.
    Corolla
    Standard rounded to broadly ovate, cucullate, slightly to markedly emarginate, with two callosities at point of attachment of the claw; wing petals obovate-falcate, shorter than the standard, with prominent auricles at the base; keel petals narrowly linear, helically coiled through several (3–4) turns.
    Stamens
    Vexillary stamen part of the sheath or sometimes free; 5 larger anthers basifixed, alternating with 5 shorter subbasifixed anthers.
    Pistil
    Ovary several-ovuled; style long, filiform, glabrous, helically coiled; stigma small and terminal.
    Fruits
    Pods shortly stipitate, oblong-ellipsoid, often somewhat clavate, markedly inflated, glabrous, smooth, dehiscent.
    Seeds
    Seeds obliquely cordiform to nearly horseshoe-shaped, with a deep hilar sinus; surface smooth to verrucose; rim aril inconspicuous.

    Images

    Distribution

    Native to:

    Angola, Botswana, Cape Provinces, Caprivi Strip, Free State, Malawi, Namibia, Northern Provinces, Zambia, Zaïre, Zimbabwe

    Bolusia Benth. appears in other Kew resources:

    First published in Hooker's Icon. Pl. 12: 57 (1873)

    Accepted by

    • Ven Wyk, B.-E., Venter, M. & Boatwright, J.S. (2010). A revision of the genus Bolusia (Fabaceae, Crotalarieae) South African Journal of Botany 76: 86-94.
    • Govaerts, R. (1996). World Checklist of Seed Plants 2(1, 2): 1-492. MIM, Deurne.

    Literature

    Flora Zambesiaca
    • Polhill in Bot. Syst. 1: 323 (1976).
    • Hutchinson, Gen. Fl. Pl. 1: 360 (1964).
    • in Hooker’s Icon. Pl. 12: t. 1163 (1873).
    Flora of Tropical East Africa
    • in Hook., Ic. Pl. 12, t. 1163 (1873)

    Sources

    Flora Zambesiaca
    Flora Zambesiaca
    http://creativecommons.org/licenses/by-nc-sa/3.0

    Flora of Tropical East Africa
    Flora of Tropical East Africa
    http://creativecommons.org/licenses/by-nc-sa/3.0

    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2018. 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 Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2018. 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

    Legumes of the World Online
    http://creativecommons.org/licenses/by-nc-sa/3.0