Costularia melicoides

The habitat of the species in Le Réunion is threatened by invasive alien species, disturbance due to human activities (e.g. illegal plant collecting of palms and orchids, littering attracting rats, population increase and pressures from increasing tourism; https://habiter-la-reunion.re/le-parc-national-de-la-reunion/), and climate change.

In Mauritius, similar threats to the habitat of the species exist, in particular due to invasive alien species, and the fragmentation and small size of some of the locations (e.g. Perrier). In Mauritius, large areas of potential habitat of the species has been cut in the 1970s for plantations (mostly pine). Some of these are now being removed/weeded and also some areas of with larger native vegetation content has been/is being weeded. Removal of alien species promotes native species recovery, including herbaceous species (Baider and Florens 2011, Florens 2013). However indiscriminate maintenance weeding is a threat to the recovering herbaceous layer (C. Baider pers. obs.). Development including inland hotels and roads, and 'eco' tourist activities (quad bikes, etc.) are a threat to areas such the Bambou Mountains, as well as deer ranching. Pollen of Cyperaceae from areas like Petrin have been more or less stable in the last 1000 years (de Boer et al. 2013).

Mauritius has 1.6% of good quality native forest left, while La Réunion has 40% (Baret et al. 2013).

The species occurs in the Parc National de La Réunion, and in the Black River Gorges National Park, the Perrier Nature Reserve and the protected areas of the Bambou Mountains on Mauritius.