Phyllanthus favieri is a shrub of 0.5-2 m high, endemic of New Caledonia and restricted to 3 northern massifs of Grande Terre : Koniambo, Kaala and Tchingou massifs. This species occurs in maquis or in forests on ultramafic substrates at an altitude range of 600 and 1,000 m asl. The main identified threats are linked to habitat damage by uncontrolled bushfires at Kaala (around 600 m) and ongoing mining activities at Kaala and Koniambo massifs and potentially by future mining activities at Tchingou massif. Its extent of occurrence (EOO) and area of occupancy (AOO) are respectively estimated to be of 863 km² and 44 km² while the number of locations is estimated to be 4. Phyllanthus favieri is therefore assessed as Endangered (EN) B1ab(i,ii,iii,v)+2ab(i,ii,iii,v) xith an estimated decline of all the concerned subcriteria.

Geographical area

Phyllanthus favieri is endemic to New Caledonia where it is restricted in 3 nothern massifs of Grande Terre: Koniambo, Kaala and Tchingou.

Population

Population size is not known.

Habitat

Phyllanthus favieri occurs in maquis or in forests on ultramafic substrates at an altitude range of 600 and 1,000 m asl.

Threats

The main identified threats are linked to habitat damage by uncontrolled bushfires around 600 m at Mt Kaala and ongoing mining activities at Kaala and Koniambo and potentially by future mining activities.

Conservation

The Phyllanthus genus is protected by legislation in Province Nord. Phyllanthus favieri does not occur in any protected area. Ex situ and in situ conservation efforts are recommended, in particular: monitoring of known subpopulations and the preservation of a viable population within delimited perimeters. It would be moreover advised to preserve patches of humid forest within delimited perimeters where this taxon is known. The variety P. favieri var. kaalaensis has been subject to cultivation by IAC (Institut Agronomique de Nouvelle-Calédonie) after a request from a mining group SMT. However the best method of generating seedlings of this species is not yet known. It is difficult to obtain viable seeds, probably due to an issue in the pollinizing process. A project to reintroduce the species in its natural habitats is being investigated.

Bibliography

Endemia.nc 2016. Faune et Flore de Nouvelle-Calédonie.

McPherson, G.; Schmid, M. 1991. Flore de la Nouvelle-Calédonie et dépendances. Volume 17 : Euphorbiaceae II Phyllanthaceae.

Munzinger J., Morat Ph., Jaffré T., Gâteblé G., Pillon Y., Rouhan G., Bruy, D., Veillon J.-M., & M. Chalopin 2020. FLORICAL: Checklist of the vascular indigenous flora of New Caledonia [continuously updated].

Experts

Assessor(s): Amice, R., Bruy, D., Butin, J., Cazé, H., Fleurot, D., Héquet, V., Lannuzel, G., Laudereau, C., Lagrange, A., Veillon, J., Garnier, D., Dumontet, V., Goxe, J., McCoy, S., Gâteblé, G.

Reviewer(s): Warimavute, G.

Facilitator(s): Warimavute, G., Meyer, S., Vandrot, H.