Taxonomy
Common name :
Cèdre rabougri
Synonyms
Dacrydium ustum Vieill.Red List Status -
Vulnerable (VU) , assessed in 03/07/2017Protected species -
in Northern Province
The subpopulations are fragmented and there is a continuing decline projected in the quality of habitat and number of mature individuals. Its extent of occurrence is estimated to be 7,657 km² and the area of occupancy is 120 km²; although this may be an under-estimate, the AOO is certainly less than 2,000 km². Therefore this species meets the criteria for listing as Vulnerable under criterion B with an estimated 10 locations. The total population size is difficult to estimate (it may be up to 10,000 mature individuals with no subpopulation containing more than 1,000 individuals). Direct threats include mining, fires and disturbance from tourists and plant collectors.
Geographical area
This species is found in isolated localities on Grand Terre in the mountains of the far south (Dzumac, Montagne des Sources), central west (Paéoua and Tchingou) and far north east (Colnett/Panie). Found from 300 to 1,250 m asl. It only occurs in association with its widespread host Falcatifolium taxoides. However, it does not occur in all Falcatifolium localities.
Population
Subpopulations are small, highly localized and fragmented. The total population size is estimated to be up to 10,000 individuals with no subpopulation containing more than 1,000 individuals.
Habitat
A small shrub which parasitises the roots of Falcatifolium taxoides in cloud forest on both acidic and ultramafic substrates. It is only found in well preserved forests.
Threats
There are direct threats from mining and its associated activities at Mt Paéoua. In other parts of its range it is threatened by an increase in fires and an overall loss of suitable habitat caused by invasive species (feral pig). It requires primary forest and is not known to survive or establish in secondary forests. It is also very sensitive to disturbance caused by tourists and others visiting the areas where it occurs. Recently, one small part of a subpopulation has been reported to be infested with an outbreak of scale insects from the genus Ceroplastes (Seyfullah et al. 2017). Their impact requires monitoring.
Conservation
This species is legally protected in province Nord but not in province Sud. It is known from several proteceted areas such as Montagne des Sources, Rivière Bleue Provincial Park and Mont Panie. The reasons of the decline of this species are not understood. Studies on the ecology of this species are recommended. Ex-situ conservation is not yet effective.
Bibliography
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].
Endemia.nc 2016. Faune et Flore de Nouvelle-Calédonie.
Seyfullah. L.J., Beimforde, C., Perrichot, V., Rikkinen, J. and Schmidt, A.R. 2017. Parasitaxus parasitized: novel infestation of Parasitaxus usta (Podocarpaceae).. Arthropod-Plant Interactions(11) , p.507-514.
Jaffré, T., Munzinger, J. & Lowry, P.P. 2010. Threats to the conifer species found on New Caledonia’s ultramafic massifs and proposals for urgently needed measures to improve their protection.. Biodiversity and Conservation (19) , p.1485-1502.
Field A.R., Bostock P.D. 2013. New and existing combinations in Palaeotropical Phlegmariurus (Lycopodiaceae) and lectotypification of the type species Phlegmariurus phlegmaria (L.) T.Sen & U.Sen.. PhytoKeys(20) , p.33-51.
de Laubenfels, D.J. 1972. Flore de la Nouvelle-Calédonie et dépendances..
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): Amice, R., Cazé, H., Dumontet, V., Fleurot, D., Garnier, D., Héquet, V., Lagrange, A., Lannuzel, G., McCoy, S., Suprin, B., Veillon, J.
Reviewer(s): Jaffré, T., Munzinger, J., Thomas, P., Gardner, M.
Contributor(s): Butaud, J., Gueugnier, C.
Facilitator(s): Maura, J., Tanguy, V.