Description:

A large species of gecko growing to a body length of 135mm and with a tail approximately the length of the body; moderately broad toes; and a colour pattern of pale to dark brown above, variably with obscure to bold, pale, V-shaped nape neck markings and scattered pale spots or blotches either side of the middle of the back.

Natural distribution:

Southern New Caledonia.

Distribution within Province Sud: Recorded from eight locations in the very far south of the island, ranging from Baie du Prony in the south, to Mt Koghis in the north.

Habitat:

Humid forest.

Threats

• high but localised level of threat to low elevation humid forest on the southeast coast through loss, modification and fragmentation of coastal forest habitat.

• high level of threat to humid forest habitat on ultramafic soils through repeated firing of adjacent maquis habitat, leading to loss and degradation of the forest edge.

• moderate to high but localised level of threat to isolated humid forest and gully forests on southern ultramafics through loss or degradation of habitat from activities associated with mining.

• potentially high level of threat to populations in humid forest with high infestation levels of the introduced Little Red Fire Ant (Wasmannia auropunctata), resulting in a significant decline in abundance.

• potentially high level of threat from exotic pests such as rats and cats (predation of adults, young & eggs) in heavily affected forest patches.

• localised but potentially intensive decline resulting from collection for illegal trade at readily accessible sites.

Conservation Status: Vulnerable

Rhacodactylus sarasinorum is a large gecko with a very restricted distribution, it is known from only seven locations in the south of the island, each representing an isolated sub-population - it is likely to occur in other closed forest patches in gullies of the Plaine des Lacs region. However, these forest patches are usually small isolates with little connectivity between them and although the number of sub-populations is likely to increase the overall real area of occupancy will remain low, and individual sub-populations will be at an increased level of risk by virtue of their very small size.

A large part of the species distribution lies within an area which is undergoing extensive change due to mining activities. Humid forest in this region has suffered and is still experiencing a decline in area of occupancy and/or quality. This in combination with the range of existing and potentially high level threats identified above and the specialised biology of the giant geckos in the genus Rhacodactylus, indicate Rhacodactylus sarasinorum satisfies the criteria to be categorised as Vulnerable, and could be moved to a higher level of conservation concern if those threats intensify.

 Department of Herpetology, Australian Museum, 6 College Street, Sydney 2000, New South Wales, Australia