Fabaceae

Decorsea R.Vig.

First published in Notul. Syst. (Paris) 14: 181 (1952)
This genus is accepted
The native range of this genus is Tanzania to S. Africa, Madagascar.

Descriptions

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

Habit
Herbs or subshrubs
Ecology
Seasonally dry tropical and subtropical woodland and woodland margins, bushland, thicket or xerophytic scrub
Distribution
southern Africa (3 spp.) and Madagascar (3 spp.)
Note
Traditionally placed in subtribe Phaseolinae, perhaps allied to Otoptera

Previous accounts of the Phaseoleae by Baudet (1978) and Lackey (1981) recognised 90 and 84 genera and c. 1540 and 1480 species respectively in the tribe. In an equivalent, i.e. traditionally held view of Phaseoleae, 89 genera and (1554)–1567–(1580) species are treated here (Table 9; Fig. 47). Changes between Baudet (1978) and this treatment are that eleven genera are now in synonymy or have subsequently been placed in Millettieae, two genera have been transferred from Desmodieae and eight new genera have been added. Vigna has traditionally been thought to comprise some 150–200 species, but Vigna sens. strict. may contain fewer than 100.

Recent molecular analyses of the tribe, however, have emphasised both the polyphyletic and paraphyletic nature of Phaseoleae as traditionally circumscribed (Bruneau & Doyle, 1990; Doyle & Doyle, 1993; Delgado Salinas et al., 1993; Bruneau et al., 1995; Doyle et al., 1997, 2000; Kajita et al., 2001; Goel et al., 2001; Lee & Hymowitz, 2001). This has required a radical realignment of elements of the phaseoloids (Table 9; Fig. 47), with at least two major clades being evident: Phaseoleae subtribes Diocleinae and Ophrestiinae which together with tribe Abreae are allied to the core-Millettieae (Fig. 45), and the remaining groups comprising a Phaseoleae sens. lat. clade. The rbcL phylogeny of Kajita et al. (2001) and the ITS analysis of Hu et al. (2002) are equivocal as to which clade subtribe Clitoriinae belongs. Phaseoleae sens. lat. also includes two traditionally independent tribes, the Desmodieae and Psoraleeae. Delimiting a recircumscribed Phaseoleae sens. strict is thus very problematic. A solution may be to recognise a broad tribe Phaseoleae, comprising the subtribes Kennediinae, Cajaninae, Phaseolinae and Glycininae, assorted basally branching genera, and tribes Desmodieae and Psoraleeae (both treated at subtribal level).

[LOWO]

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

Morphology General Habit
Perennial twining herbs; rootstock possibly tuberous
Morphology Leaves
Leaves pinnately 3-foliolate; stipules and stipels present
Morphology Reproductive morphology Flowers
Flowers in small axillary 4–10 (–20)-flowered clusters on reduced side branches often appearing when the plant is quite leafless
Morphology Reproductive morphology Flowers Calyx
Calyx appearing 4-lobed, the upper pair of lobes united into a low rounded lip
Morphology Reproductive morphology Flowers Corolla
Corolla medium-sized; standard oblate, reflexed, glabrous, only slightly auriculate; appendages 2 or obsolete; wings obovate-oblong; keel incurved through 360°, the beak twisted
Morphology Reproductive morphology Flowers Androecium Stamens
Vexillary stamen free; anthers ± uniform
Morphology Reproductive morphology Flowers Gynoecium Pistil
Ovary linear, ± 9–14-ovuled; style consisting of two parts, an apical, thickened, strongly curved glabrous part and a tenuous flexible basal part of approximately equal length; stigma capitate, terminal, surrounded by a ring of branched or simple hairs
Morphology Reproductive morphology Fruits
Pods linear, almost straight, not septate
Morphology Reproductive morphology Seeds
Seeds oblong or narrowly oblong, compressed; rim-aril scarcely to slightly developed but a small cartilaginous funicle-remnant persistent.
[FTEA]

Leguminosae, B. Mackinder, R. Pasquet, R. Polhill & B. Verdcourt. Flora Zambesiaca 3:5. 2001

Morphology General Habit
Perennial twining herbs; rootstock usually tuberous.
Morphology Leaves
Leaves pinnately 3-foliolate; leaflets sometimes lobed; stipules and stipels present.
Morphology Reproductive morphology Flowers
Flowers in small axillary 4–10(20)-flowered clusters on reduced side branches or swollen or elongated nodes of the inflorescence rhachis, often appearing when the plant is quite leafless; bracteoles foliaceous (sometimes large outside the Flora Zambesiaca area), deciduous.
Morphology Reproductive morphology Flowers Calyx
Calyx appearing 4- or 5-lobed, the upper pair of lobes united into a low rounded or notched lip.
Morphology Reproductive morphology Flowers Corolla
Corolla medium sized; standard oblate, reflexed, glabrous, only slightly auriculate with appendages 2 or obsolete; wings obovate-oblong; keel incurved through 360°, the beak twisted.
Morphology Reproductive morphology Flowers Androecium Stamens
Vexillary stamen free; anthers ± uniform.
Morphology Reproductive morphology Flowers Gynoecium Pistil
Ovary linear, c. 9–16-ovuled; style consisting of two parts, an apical, thickened, strongly curved glabrous part and a tenuous flexible basal part of approximately equal length; stigma capitate, terminal, surrounded by a ring of branched or simple hairs.
Morphology Reproductive morphology Fruits
Pods linear, almost straight, not septate.
Morphology Reproductive morphology Seeds
Seeds oblong or narrowly oblong, compressed; rim aril scarcely to slightly developed but a small persistent cartilaginous funicle remnant.
[FZ]

Uses

Use
Seeds and tubers said to be edible
[LOWO]

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 Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Legumes of the World Online

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

  • World Checklist of Vascular plants (WCVP)

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0