The vlei ink-flower is a
hairless or nearly hairless, hemiparasitic, high perennial
herbaceous plant, with angular stems having four flat sides, which are creeping, straggling or upright, that may have side branches or not, and sometimes there are a few glandular hairs. These stems carry few distanced leaves arranged oppositely or nearly so, which are approximately
linear, widest at midlength, with a pointed cartilaginous tip, with a very short leaf stalk or seated, glossy, the margin entire or with a few teeth, rather thick, the veins sunken, long and wide. Its flowers are long, reminiscent of a
Phlox. These are set individually in the axil of a bract on a slender but rigid
pedicel of long, which does not carry any bracts subtending the flower. The five
sepals are fused into a high bell- to cone-shaped calyx tube, with ten veins, and ending in five almost lanceolate keeled lobes, that become narrower towards their tips and are long. The corolla is white, pinkish or purple and consists of five
petals, which are fused into a curved, cylindrical long
corolla tube. Above the "limb", the corolla becomes an approximately flat disk in diameter, that splits into five ovate lobes with a rounded margin, with the two lobes at the outside of the curve merged over a greater length than the others. Inside the corolla tube are five
stamens with softly hairy filaments topped by long hairless, oblong anthers. The style does not reach the stamens, and is topped by a thickened, pointy
stigma. The fruit is a hairless, short, oblique, slightly compressed, oval capsule of long and wide, topped by a short and obliquely beak, and has
coriaceous valves. The plant discolors to black when drying. == Taxonomy ==