It’s not a Western Hemisphere problem, but an international group of scientists, including botanists at the University of Oxford’s Botanic Garden, has issued an urgent call for coordinated action to save the iconic genus Rafflesia, which contains the world’s largest flowers.

At more than a yard in circumference in bloom, Rafflesia plants are a parasite that take over its hosts with its many tendrils. After that, a cabbage-head style bud blossoms into a flower that smells like rotting flesh, hence its nickname “corpse flower.”

A new study — published in Plants, People, Planet — found:

• Most of the 42 Rafflesia species face extinction.

• Lack of protection at local, national and international levels means that remaining populations are under critical threat.

• Building on local success stories, researchers say an urgent action plan is necessary.

Rafflesia is one of the greatest botanical enigmas, and has aroused curiosity among scientists for centuries. The parasitic plant infects tropical vines in jungles across Southeast Asia (Brunei, Indonesia, Malaysia, the Philippines and Thailand). For most of its life cycle, Rafflesia is hidden from sight, existing as a system of thread-like filaments that invades its host.

Then, at unpredictable intervals, the parasite produces a cabbage-like bud that breaks through the vine’s bark and eventually forms a giant, five-lobed flower that can be a little more than a yard across.

Because of its elusive life cycle, scientists say Rafflesia remains poorly understood, and new species are still being recorded. Due to this, scientists have established the first coordinated global network to assess the threats and better understand its vulnerability.

Researchers are recommending that all Rafflesia species be immediately added to the International Union for Conservation of Nature.

The new study found that most of the 42 species are severely threatened, yet just one of these is listed in the International Union for Conservation of Nature’s Red List of Threatened Species. Additionally, 67% of the plants’ habitats are unprotected and at risk of destruction.

Scientists are also looking for ways to propagate the species outside its native habitat and the introduction of new ecotourism opportunities to better promote the plant.

Research is ongoing in the Philippines to study the mysterious plant and find ways to protect it, according to Mongabay. Environmental tourism is helping to spread awareness and promote the plant in Indonesia, described in Telapak.

Chris Thorogood, deputy director of the University of Oxford Botanic Garden and an author of the study, said the need for conservation of this species is critical.

“This new study highlights how the global conservation efforts geared towards plants — however iconic — have lagged behind those of animals. We urgently need a joined-up, cross-regional approach to save some of the world’s most remarkable flowers, most of which are now on the brink of being lost.”