Vachellia tortilis (Forssk.) Galasso & Banfi

Leguminosae, J.P.M. Brenan. Flora Zambesiaca 3:1. 1970

Morphology General Habit

Tree 4-21 m. high, occasionally (probably not in our area) a bush 1 m. high; crown flat or spreading;10 bark grey to black, fissured; young branchlets glabrous to densely pubescent, going brown to purplish-black.

Morphology Leaves Stipules

Stipules spinescent, some short ± hooked and up to c. 5 mm. long, mixed with other long straight whitish ones to c. 8(10) cm. long; “ant-galls” and other prickles absent.

Morphology Leaves

Leaves; rhachis short, 2 cm. long or less; pinnae 2-10 pairs, 2-17 mm. long; leaflets 6-19 pairs per pinna, usually very small, 0.5-2.5(6) mm. long, ciliate to glabrous.

Morphology Reproductive morphology Flowers

Flowers cream or whitish, in axillary heads 5-10 mm. in diam. on peduncles 0.4-2.4 cm. long; involucel in the lower half of the peduncle.

Morphology Reproductive morphology Fruits

Pods contorted or spirally twisted, longitudinally veined, tomentellous to glabrous.

Morphology Reproductive morphology Seeds

Seeds olive- to red-brown, 7 x 4.5-6 mm., smooth, elliptic, compressed; areole 5-6 x 3-4 mm.

International Legume Database and Information Service

Conservation

Not Threatened

Ecology

Africa: Sahara regional transition zone; woodland., Zambezian woodland, Somalia-Masai bushland and thicket, Kalahari-Highveld regional transition zone; wooded grassland., Sudanian woodland, Karroo-Namib shrubland, Sahel regional transition zone - wooded g

Morphology General Habit

Perennial, Not climbing, Shrub/Tree

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

Morphology General Habit

Tree 4–21 m. high, occasionally (probably not in our area) a bush 1 m. high; crown flat or spreading;bark grey to black, fissured.

Morphology Branches

Young branchlets glabrous to densely pubescent, going brown to purplish-black.

Morphology Leaves Stipules

Stipules spinescent, some short ± hooked and up to about 5 mm. long, mixed with other long straight whitish ones to about 8(–10) cm. long; “ant-galls” and other prickles absent.

Morphology Leaves

Leaves:rhachis short, 2 cm. long or less; pinnae 2–10 pairs, 2–17 mm. long; leaflets 6–19 pairs per pinna, usually very small, 0.5–2.5(–6) mm. long, ciliate to glabrous.

Morphology Reproductive morphology Flowers

Flowers cream or whitish, in axillary heads 5–10 mm. in diameter on peduncles 0.4–2.4 cm. long.

Morphology Reproductive morphology Fruits

Pods contorted or spirally twisted, longitudinally veined, tomentellous to glabrous.

Morphology Reproductive morphology Seeds

Seeds olive- to red-brown, smooth, elliptic, compressed, 7 mm. long, 4.5–6 mm. wide; areole 5–6 mm. long, 3–4 mm. wide.

Distribution

Algeria to Egypt (? Palestine) and Arabia southwards to South Africa

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

Morphology General Habit

Tree 4–21 m, mostly with flat crown; young branchlets glabrous to densely pubescent

Morphology General Spines

Stipular spines in pairs, some short, hooked and up to 5 mm long, mixed with other straight slender ones up to 10 cm long

Morphology Leaves

Pinnae 2–10 pairs; leaflets 6–22 pairs, 0.5–4(–6) x 0.5–1 mm

Morphology Reproductive morphology Flowers

Flowers whitish, in heads; peduncles 0.4–2.4 cm long, with the involucel in the lower half

Morphology Reproductive morphology Flowers Calyx

Calyx 1–2 mm long

Morphology Reproductive morphology Flowers Corolla

Corolla 1.5–2.5 mm long

Morphology Reproductive morphology Fruits

Pods contorted, spirally twisted, or rarely almost straight, indehiscent or very slowly dehiscent, 0.6–1(–1.3) cm wide, longitudinally veined, glabrous to tomentellous or villous

Morphology Reproductive morphology Seeds

Seeds 4–7 x 3–6 mm, compressed; areole 3–6 x 2–4 mm.

Note

Var. crinita is a form with pods clothed with 1–3 mm long spreading hairs. In Somalia it is only known from S1, but plants with similar indumentum of the pods are known also from Kenya and Tanzania. A. tortilis in general is very variable in Somalia and at least two forms here tentatively placed in subsp. spirocarpa may well represent other taxa: (1) In N3 there are forms with glabrous pods like subsp. raddiana, but with hairy leaves like subsp. spirocarpa. They agree quite well with subsp. heteracantha (Burch.) Brenan in the dry regions of southern Africa, but I hesitate in placing them in this taxon without further evidence. (2) In C1 and C2 there is a shrubby form with almost straight, pubescent and glandular pods, up to 15 x 0.5 cm, and hairy leaves. This might be best treated as a subspecies of its own, but also here further studies are needed.