Harveya squamosa

Harveya squamosa, in Afrikaans known as the jakkalskosinkblom (jackal food inkflower), is an orange-flowering root parasite, a fleshy perennial reaching 15 cm in height.

The plant attaches underground to restio or daisy shrublet roots for sustenance, having no photosynthetic capacity itself. Perennial parasites attach to perennial hosts, annuals to annuals.

The Harveya induces proliferation of inner tissue by the host plant at the point of attachment, the haustorium, where it connects firmly for nutrient transfer. Harveya plant surfaces have sunken stomata that open and excrete water vapour, creating suction for receiving juice from the host.

The sessile, tubular flowers grow in a dense, erect and hairy spike at ground level. The calyx is tubular and two-lipped, ending in five short lobes. The angled-out corolla tube widens and curves down slightly, yellow on its throat. The five petals are oblique, about 4 cm long.

The four stamens end in two-lobed anthers, a sterile and a fertile one. The sterile one acts as a spur, aiding pollen release before stigma growth obstructs the way; a common feature in Harveya flowers.

Flowering happens from late winter to early summer. There is also a rare sulphur-yellow flowering form of H. squamosa.

The species distribution is in the Western Cape from the Cape Peninsula to Bredasdorp and along the west coast to at least Clanwilliam.

The plants grow in the open on flats and lower slopes of deep, very sandy soils. The species is not considered to be threatened in its habitat early in the twenty first century (Manning, 2009; Manning and Goldblatt, 1996; Bond and Goldblatt, 1984; Visser, 1981; http://redlist.sanbi.org).