Orthosiphon schimperi


Orthosiphon schimperi, commonly called the purple piccadill, is a sub-Saharan species of flowering plant in the family Lamiaceae. It closely resembles the Asia-bound species Orthosiphon rubicundus, and some sources misapply the latter name in parts of Africa.

Description

This is a perennial herb with a thick woody rootstock extending both downward and laterally, growing to about tall, not or only weakly aromatic. Stems are numerous, erect and square in cross-section, usually unbranched below the flowering shoots, and variably hairy, especially along the angles.
Leaves are subsessile to shortly stalked above and more distinctly stalked below, with ovate to elliptic blades long and wide, coarsely toothed, and variably hairy, particularly along the veins beneath.
The inflorescence is initially dense, with flower clusters touching, later becoming more spaced in fruit; small bracts are long. The calyx is typically flushed reddish-brown to purple, long at flowering and elongating to in fruit. The corolla is usually pale pink, occasionally white or mauve, long, with a straight tube and a hooded lower lip that encloses the stamens.
The nutlets are brown, broadly egg-shaped, about long, and produce a small amount of mucilage when wet.

Identification

The African species that Orthosiphon schimperi most closely resembles is Orthosiphon thymiflorus. In eastern Africa, the former species can be distinguished by, among other things, its larger fruiting calyx, which is a purple– red colour throughout. In the latter species, the upper lip of the calyx is purple, while the lower lip is green.

Distribution and habitat

Orthosiphon schimperi is widespread in tropical Africa, having been recorded in Angola, Benin, Burkina Faso, Burundi, Cameroon, the Democratic Republic of the Congo, Eritrea, Ethiopia, Ghana, Guinea, the Ivory Coast, Kenya, Malawi, Mali, Mozambique, Nigeria, Rwanda, Somalia, South Sudan, Tanzania, Togo, Uganda, Zambia, Zimbabwe, and the South African province of Limpopo. It grows in open, grassy woodland, especially in more moist places.

Etymology

Orthosiphon schimperi is named for Wilhelm Schimper, the German botanist who first collected it on Mount Soloda in Tigray in 1838. Schimper spent over forty years collecting specimens in Ethiopia and is thought to have introduced more African plants to science than anyone before or since. Scores of other taxa bear his name.