A life in the dark
Cytinus hypocistis is a holoparasite, a plant that derives all of its nutrients and water from a host. It has no chlorophyll, leaves, stems, or external roots of its own. For most of its perennial life, it exists as a network of filaments, similar to fungal hyphae, growing entirely inside the roots of its host plant—a condition known as being an endoparasite. This internal, vegetative body penetrates the host's tissues, developing a vascular system to absorb everything it needs to survive. The parasite specifically targets shrubs of the Cistaceae family, most commonly the rockroses (Cistus species) and sometimes Halimium species. Studies show it can be highly host-specific, preferring certain species like Cistus monspeliensis even when other potential hosts are more abundant.
The only part of Cytinus hypocistis that ever emerges from the ground is its inflorescence, a cluster of flowers that erupts through the host's root tissue in the spring, typically from April to May. These flowering shoots, which grow no more than eight centimeters high, are covered in fleshy, scale-like leaves. The plant is monoecious, meaning each inflorescence has both male and female flowers. The male flowers are typically located in the center of the cluster, with the female flowers arranged around the edges. The flowers themselves are tubular, with a four-toothed yellow perigonium, and sit atop bright red or yellowish bracts.