Researchers from the Hainan Academy of Forestry have rediscovered the Hainan Homalomena, a plant species unique to Hainan, in Haikou’s volcanic lava wetland.

The species hadn't been observed in the wild for 90 years, making the discovery a significant breakthrough for biodiversity conservation on the island.

Homalomena hainanensis is a perennial herb belonging to the genus Homalomena within the Araceae family. Endemic to China, it is exclusively found on Hainan Island, where it usually grows in shaded mountain forests.

The plant was first collected in Baoting in central Hainan in 1936 by botanist Liu Xinqi, who created the species’ only type specimen, now kept at the Guangxi Herbarium. In 1977, arum specialist Li Heng identified it as a new species within Homalomena, and no wild populations have been documented since.

The rediscovery was made during a field survey of plant diversity in the volcanic lava wetlands of northern Hainan. Researchers found a wild population of about 300 plants growing beneath litchi and bamboo in rich volcanic soil. Most were blooming and looked healthy. However, since all known sites lie outside protected zones and are subject to regular human activity, there is a clear need for enhanced conservation efforts.

Despite its status as an endangered species, there had been no documented information on the ecology, population status, or distribution of the Hainan Homalomena in Haikou prior to this discovery. The recent survey documented its flowers, stems, leaves, and habitat, offering important information on its taxonomy, preferred habitat and growth traits, and the health of its wild population.

Experts state that the discovery highlights the unique vegetation of Haikou’s volcanic lava wetlands and showcases Hainan’s recent advancements in biodiversity conservation. Researchers plan to keep monitoring plant diversity, conduct broader field surveys, and gather germplasm for ex situ conservation to support ongoing wetland biodiversity protection and ecological restoration in Haikou.