Taxonomy

Pichonia munzingeri Gâteblé & Swenson
endemique
UICN

Red List Status -

Critically Endangered (CR) , assessed in 02/05/2019

Even if only preliminary results are available, Pichonia munzingeri has a unique phylogenetic position, being the sister species to all congeners in New Caledonia and, hence, the oldest lineage of its kind in the territory. It has been found in only one location with two very small subpopulations on both sides of Oumbéa Creek separated by less than 600 m. The main threat to Pichonia munzingeri is the frequent anthropogenic fires which are likely to further reduce the populations size. The other threats are the establishement of the catchment that could have destroyed some individuals and logging.The calculated Area of occupancy (AOO) value is only 4 km² (grid of 2 × 2 km) a value also applicable for Extent of Occurrence (EOO). Allin all, effective in situ conservation appears very important to maintain high genetic diversity and we therefore suggest that P. munzingeri is assigned a preliminary status of “Critically Endangered” [CR B1ab(ii,iii,iv,v)+2ab(ii,iii,iv,v); C2a(i); D].

Geographical area


Pichonia munzingeri is so far only known from the Oumbéa Creek, one of the tributaries of La Coulée River within the Mont-Dore municipality

Population


It has been found in only one location with two very small subpopulations on both sides of Oumbéa Creek separated by less than 600 m. The upper subpopulation has some 30 individuals whereas only three have been located in the lower one.

Habitat


It grows in degraded maquis and rainforest remnants, on the lower and wettest parts of the slopes, though it is not a riparian species. It occurs on ultramafic substrate with peridotites rocks.

Threats


The upper subpopulation has some 30 individualswhereas only three have been located in the lower one. In uppper subpopulation, P. munzingeri grows along a track to awater catchment area built in 1997 that was expanded in 2001.It is possible that some individuals were removed when the catchment area was established. Oumbéa Creek, Coulée River,and the Montagne des Sources protected area were severelydamaged by a deliberately set fire at the end of the 2005 dry season that burned around 43 km². Both subpopulations of P. munzingeri must have been badly impacted by this anthropogenic fire because most plants are regrowth from burnt stumps and not juveniles. The lower subpopulationis adjacent to a popular water hole where people enjoy swimming during the hot season and where the vegetation (including the new Pichonia) is regularly cut down for setting up camp fires. After the 2005 Montagne des Sources severe fire, the ground has become infested by Pteridium esculentum(G. Forst.) Cockayne, a species that is highly flammable in the dry season and well known to facilitate the spread of new fires (Jaffré et al., 1998). Hence, the main threat to Pichonia munzingeri is the frequent anthropogenic fires which are likely to further reduce the populations size.

Conservation


An effective in situ conservation appears very important to maintain high genetic diversity

Bibliography


Gâteblé, G. & Swenson, U. 2019. Pichonia munzingeri (Sapotaceae), a new and rare micro-endemic species from New Caledonia. Candollea(74(1)) , p.1-7.

Experts


Assessor(s): Amice, R., Bruy, D., Butin, J., Cazé, H., Fleurot, D., Garnier, D., Gâteblé, G., Héquet, V., Laudereau, C., McCoy, S., Suprin, B., Vandrot, H., Veillon, J.

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


Geographical distribution