Taxonomy
Phasmasaurus tillieri
Common name :
Le scinque de Tillier des maquis
Red List Status -
Near Threatened (NT) , assessed in 11/12/2017Protected species -
in Southern Province , in Northern Province
Although the extent of occurrence and area of occupancy are well below the thresholds for a threatened category, Phasmasaurus tillieri does not qualify at present because the number of known locations is just exceeded, the populations are probably not as fragmented as they appear, and there are no data on population trends. However, the threats posed by the rapidly expanding mining industry in the Grand Sud and Tontouta Valley, afforestation in the Grand Sud, and the recent naturalization of the ant Anoplolepis gracilipes combine to mean this situation could deteriorate quickly. Therefore, this species is listed as Near Threatened as it almost qualifies for listing under criterion B1ab(iii)+2ab(iii).
Geographical area
This species is endemic to Province Sud, New Caledonia. It is known from thirteen localities across the southern part of Grande Terre between the Tontouta Valley and Mt Humboldt in the north and Baie de Prony and Port Boise in the south. It occurs at elevations of up to 1,000 m. The extent of occurrence is estimated at 1,933 km2, and the area of occupancy at 96 km2.
Population
No quantitative data are available on population size and trends for this species. Although recurrent wildfires are likely to have degraded maquis habitats (through simplification of the vegetation) and caused a reduction in skink population density, these fires have at the same time probably greatly increased the area of maquis shrubland habitat available through the destruction of closed forests. In the Grand Sud habitat has been lost to mining and afforestation. Phasmasaurus tillieri is still relatively common at some sites.
Habitat
This species inhabits open maquis, wetland maquis and grasslands. It is diurnal, terrestrial and is active in sunlight. It shelters beneath stones and in dense vegetation. It forages on the ground; usually basks low (<1 m above ground) in shrubs, grasses and sedges (occasionally on rocks).
Threats
Phasmasaurus tillieri is at constant risk to habitat degradation and loss arising from the frequent wildfires that burn maquis shrubland habitats. In the Grand Sud extensive areas of maquis habitat are under threat from the expanding mining industry and from afforestation, and mining also threatens habitat in the Tontouta Valley–Mt Vulcain area. In woody maquis, this species may be at risk to the introduced ant Wasmannia auropunctata, which is known to decimate lizard populations (Jourdan et al. 2000, 2001). It is also likely to be at risk to another invasive ant, Anoplolepis gracilipes, which has recently colonized the Grand Sud area. Predation by introduced mammals (rodents and cats) is an ever-present threat.
Conservation
This species is protected in Province Nord under Code de l'environnement de la Province Nord (Délibération No. 306-2008/APN, 24 October 2008) and in Province Sud under Code de l'environnement de la Province Sud (Délibération No. 25-2009/APS, 20 March 2009). It is present in Parc Provincial de la Rivière Bleue, Mont Mou and Mont Humboldt. No active conservation management is currently being undertaken.
Bibliography
Endemia.nc 2016. Faune et Flore de Nouvelle-Calédonie.
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.
Hallé N.; Aubréville A.; Leroy J. F.; 1977. Flore de la Nouvelle-Calédonie et dépendances. Volume 08 : Orchidaceae.
Experts
Assessor(s): Butin, J., Laudereau, C., Amice, R., Fleurot, D., Frayssinet, I., Garnier, D., Letocart, D., Letocart, I.
Reviewer(s): Tanguy, V.
Contributor(s): Faria, E.
Facilitator(s): Chanfreau, S.