Catophractes alexandri D.Don

Genus and Family

Catophractes alexandri is the only species in the genus Catophractes, a member of the plant family Bignoniaceae.

Growth Form

It grows as a spiny shrub or small tree reaching up to 3 m in height.

Distribution Range

This species occurs in hot, low-rainfall regions of Namibia, the Northern Cape, the Kalahari Desert, Botswana, western Zimbabwe, and Limpopo.

Habitat Preferences

It prefers calcrete, limestone outcrops, and limestone soils, and often forms pure stands. When not growing alone, it typically associates with Colophospermum mopane, Rhigozum virgatum, Phaeoptilum spinosum, and Acacia nebrownii.

Parasite Hosts

It is parasitized by several species of the genus Tapinanthus.

Etymology of Epithet

Its specific epithet alexandri honors James Edward Alexander, a Victorian soldier and explorer.

Etymology of Genus

The generic name refers to the fact that the plant’s leaves and flowers emerge from below its paired, decussate, opposite spines.

Leaf Characteristics

Its leaves are either tufted (fascicled) or opposite, are densely grey-tomentose, simple, and elliptic to obovate in shape. They grow up to 4 cm long, with coarsely dentate or scalloped margins.

Flowering Trigger

After rain events, the plant produces fragrant, showy 5-lobed flowers that are roughly 10 cm long.

Flower Coloration

Flowers are white or pink, with a yellow throat.

Flower Internal Features

Inside the flower tube, there is a broad, villous band below the point where the stamens attach. The calyx is tubular, has linear teeth, and is slit along one side.

Fruit Structure

The fruit of Catophractes alexandri is a flattened, woody capsule around 10 cm long, with a warty surface.

Fruit Dehiscence

The capsule dehisces across its flat faces into two equal parts.

Fruit Sound Production

Mature old fruits hang downward, and the two hollow halves tap against one another like castanets, producing a distinctive clicking sound in light wind.

Seed Features

Seeds of this species are papery and winged.

Initial Formal Description

This species was first formally described in publications from 1839: "Ann. Nat. Hist." ii. 375, and "Proc. Linn. Soc." i. 4.

Subsequent Published Descriptions

Later descriptions appeared in "Trans. Linn. Soc." xviii. (1841) 307, t. 22; "DC. Prodr." ix. 233; Kuntze in "Jahrb. Bot. Gart. Berl." iv. (1886) 270; Engl. in "Engl. Jahrb." x. 255; and K. Schum. in "Engl. & Prantl, Pflanzenf." iv. 3B, 233.

Medicinal Uses Overview

This species has several documented medicinal uses.

Stomach Complaint Treatment

The root is chewed to treat stomach complaints.

Pediatric Abdominal Pain Treatment

When combined with the root of Polygala leptophylla Burch., it is prepared as a decoction to treat abdominal pain, especially in children.

Cold and Cough Treatment

Infusions and decoctions made from the leaves, roots, and bark are used to treat colds and coughs.