Abrus Adans.

M. Thulin et al. Flora of Somalia Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit

Woody subshrubs or lianes

Morphology Leaves

Leaves paripinnate; leaflets numerous, opposite

Morphology Reproductive morphology Flowers

Flowers small in clusters forming axillary or terminal inflorescences

Morphology Reproductive morphology Flowers Calyx

Calyx subtruncate to shortly 5-toothed

Morphology Reproductive morphology Fruits

Pod linear or oblong, usually compressed.

Distribution

About 17 species throughout the tropics.

Flora Zambesiaca Leguminosae subfamily Papillionoideae by D.K. Harder

Morphology General Habit

Stipules small, usually persistent; stipels filiform; rachis projecting beyond the last pair of leaflets. Stipules small, usually persistent; stipels filiform; rachis projecting beyond the last pair of leaflets.

Morphology Reproductive morphology Inflorescences

Inflorescence axillary or terminal, the flowers in fascicles on short reduced branchlets, often arranged unilaterally on the rachis, or rarely sessile in the axils; bracts and bracteoles present. Inflorescence axillary or terminal, the flowers in fascicles on short reduced branchlets, often arranged unilaterally on the rachis, or rarely sessile in the axils; bracts and bracteoles present.

Morphology Reproductive morphology Flowers

Flowers small, white, yellow, pink or dark purple. Flowers small, white, yellow, pink or dark purple.

Morphology Reproductive morphology Flowers Corolla

Standard ovate to round, with a short broad claw, glabrous. Standard ovate to round, with a short broad claw, glabrous.

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary subsessile, many-ovuled; style not bearded; stigma capitate.

Morphology Reproductive morphology Flowers Androecium Stamens

Upper stamen absent. Upper stamen absent.

Morphology Reproductive morphology Flowers Gynoecium Pistil

Ovary subsessile, many-ovuled; style not bearded; stigma capitate.

Morphology Reproductive morphology Fruits

Pods linear or oblong, subturgid or compressed, or ± septate. Pods linear or oblong, subturgid or compressed, or ± septate.

Morphology Reproductive morphology Seeds

Seeds subglobose or ellipsoid and compressed, sometimes bright red and black; rim aril sometimes developed, usually minute or absent. Seeds subglobose or ellipsoid and compressed, sometimes bright red and black; rim aril sometimes developed, usually minute or absent.

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

Habit

Climbing subshrubs (sometimes lianas) or herbs

Ecology

Seasonally dry tropical forest, woodland, wooded grassland, grassland, shrubland, bushland and thicket, often in open disturbed vegetation, along margins and in seasonally wet or in rocky areas

Distribution

Africa (c. 8 spp.), Madagascar (5 spp.), India (1 sp.) and Indo-China (1 sp.), 2 spp. widespread in the Old World (both also occur - probably introduced - in the New World)

Note

Some species are difficult to classify and species limits have been much discussed, with Verdcourt (1970b) and Breteler (1960; 1994a) putting opposing opinions; the classification of Verdcourt is followed here

The tribal placement of the isolated genus Abrus (with 17 species) has long been problematic (Polhill 1981e: 243–244). The most recent molecular analyses of Doyle et al., 2000; Hu, 2000; Hu et al., 2000; Kajita et al., 2001; Wojciechowski, 2003 & Wojciechowski et al., 2004), however, consistently place Abrus near the base of the clade comprising the core-Millettieae and various elements excluded from Phaseoleae sens. lat. (Figs. 45–47). This basally branching position together with the unusual combination of paripinnate leaves, 9 stamens and a chemical profile of tryptophane-derived alkaloids (abrine and hypaphorine) and pyridine-based alkaloids (precatorine and trigonelline), supports the maintenance of Abrus as a separate monogeneric tribe for the present. Improved understanding of relationships is likely to result from greater sampling within the millettioid-phaseoloid complex.

The Abreae are predominantly Afro-Madagascan in distribution with 3 species endemic to the Horn of NE Africa. The remaining species are Asian and 2 species are pantropical. New World representatives (from Amazonian Brazil and Venezuela) of the pantropical A. melanospermus Hassk. subsp. tenuiflorus (Benth.) D. Harder [= A. pulchellus Wall. ex Thwaites subsp. tenuiflorus (Benth.) Verdc.]), are possibly distinct from Old World material of this subspecies (Verdcourt, 1970b).

George R. Proctor (2012). Flora of the Cayman Isands (Second Edition). Royal Botanic Gardens, Kew

Morphology General Habit

Slender woody vines; leaves even-pinnate, lacking a terminal leaflet, the rhachis terminating in a bristle; leaflets numerous; stipels absent

Morphology Reproductive morphology Flowers

Flowers in short racemes, terminal or axillary on short branches, the pedicels clustered at nodes of the raceme

Morphology Reproductive morphology Flowers Calyx

Calyx truncate or very shortly 5-toothed; corolla usually pinkish or whitish; standard ovate, the short claw adherent to the stamen-tube; wings oblong-falcate; keel curved, longer than the wings

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens 9, united into a sheath split above; anthers all alike

Morphology Reproductive morphology Flowers Gynoecium Ovary

Ovary subsessile; style short, incurved, with capitate stigma; ovules numerous

Morphology Reproductive morphology Seeds

Pod somewhat compressed, 2-valved, with partitions between the seeds.

Distribution

A small pantropical genus of about 5 species.