Huernia zebrina is a succulent plant belonging to the family Apocynaceae. Owing to its distinctive flower shape and vivid patterns, it is also known as the "lifesaver plant." The flower of Huernia zebrina has a flat corolla formed by the fusion of five star-shaped petals. At its center develops a greatly elevated ring-shaped corona, which appears like a three-dimensional torus—one of the most striking features of this species.

Corona
In flowers of the genus Huernia, an accessory structure called the corona develops at the base of the petals. In Huernia zebrina, this corona is extremely enlarged, forming a raised, circular ring.

Torus-like morphology
From the outside, it resembles a circular torus. Inside the ring lies the gynostegium, which functions as a guide for visiting insects.

Attraction of pollinators
By forming a donut-shaped three-dimensional structure, the corona acts as a visual "target," directing insects toward the flower’s center.

Landing and guiding mechanism
The inner opening allows insects to enter more easily, thereby facilitating the attachment of pollinia to their bodies.

Pseudocarrion effect
The glossy surface and striped pattern evoke the appearance of meat or carrion, serving as a visual trick that attracts flies and other insects typically drawn to decaying matter.