Taxonomy
Red List Status -
Near Threatened (NT) , assessed in 08/09/2017
Oxera coriacea is an endemic shrub or robust small tree of New Caledonia, distributed from the centre to the southern part of Grande Terre. Found in dense humid forest and scrubland on ultramafic rocks, this species occurs from 10 to 1,000 m asl. Its area of occupancy (AOO) and extent of occurrence (EOO) are 72 km² and 2,748 km², respectively. The number of location is estimated to be 12 and it is estimated that some subpopulations (Sarraméa and Kouaoua) can completely dissapear if no effort of conservation is made to protect this species. Continuous declines in population size, number of locations, Area of Occupancy (AOO) and habitat quality are projected due to mining activities, agriculture and habitat degradation caused by rusa deer (Rusa timorensis). Therefore, O. coriacea is listed as Near Threatened (NT), close to VU under criteria B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v).
Geographical area
O. coriacea is endemic to New Caledonia where it is distributed from the centre to the southern part of Grande Terre (New Caledonia).
Population
Population size is unknown but field surveys show a small population size with no regeneration is observed.
Habitat
O. coriacea occurs in dense humid forest and scrubland on ultramafic rocks from 10 to 1,000 m asl.
Threats
Despite a large distribution area, O. coriacea could be impacted in the long term by mining activities (Vulcain (SMGM), Kouaoua (SLN)), agriculture as well as invasive animal species, such as Rusa deer (Rusa timorensis).
Conservation
This species is not protected by any legislation in New Caledonia, but it occurs in three protected areas: Mont Do, Dumbéa and on the edge of Haute Dumbéa (Dzumac). This species is cultivated at the IAC (Institut Agronomique de Nouvelle-Calédonie) nursery of Saint-Louis with only a few number of individuals.
Bibliography
Gâteblé, G. 2016. Flore ornementale de Nouvelle-Calédonie.
Endemia.nc 2016. Faune et Flore de Nouvelle-Calédonie.
Mabberley DJ, de Kok RPJ. 2004. Labiatae. In: Morat P,ed. Flore de la Nouvelle-Calédonie et dépendance.
Barrabé L, Karnadi-Abdelkader,G, Ounemoa,J,de Kok RPJ., Robert N, Gâteble,G. 2015. Recircumscription of Oxera (Lamiaceae: Ajugoideae) ta include Faradaya based on molecular and anatomical data. Botanical Journal of the Linnean Society(179) , p.693-711.
Morat, P.; Jaffré, T.; Tronchet, F.; Munzinger, J.; Pillon, Y.; Veillon, J.-M. and Chalopin, M. 2012. Le référentiel taxonomique Florical et les caractéristiques de la flore vasculaire indigène de la Nouvelle-Calédonie [The taxonomic database « FLORICAL » and characteristics of the indigenous flora of New Caledonia]. Adansonia sér 3(34) , p.177-219.
Experts
Assessor(s): Gâteblé, G., Barrabé, L., Fleurot, D., Amice, R., Cazé, H., Bruy, D., Héquet, V., Vandrot, H., Butin, J., Mandaoué, L., Haverkamp, C., Dumontet, V., Laudereau, C.
Reviewer(s): Meyer, S.
Facilitator(s): Warimavute, G., Tanguy, V.