Description:

A large species of gecko growing to a body length of 255mm, with a tail approximately as long as the body when young, but nearly always lost and regrown as a much smaller tail in adults; broad toes with extensive webbing, and extensive loose folds of skin along the ventrolateral margin of the body; and a colour pattern that is typically greyish, greenish, through to brown, with lighter spots or pale blotches on the body.

Natural distribution:

Widespread throughout New Caledonia over a wide altitudinal range, and the Ile des Pins and adjacent islands.

Distribution within Province Sud: Recorded from seven locations in the south of the Province, and from the Ile des Pins and several offshore islands.

Distribution within Province Nord: Recorded from a number of locations up the east coast with several records from the central mountain chain.

Habitat:

Humid forest.

Threats:

• extremely high level of threat to insular populations (Isle of Pines and surrounding islets) posed by collection for illegal trade.

• high level of threat from exotic pests such as rats and cats (predation of adults, young & eggs), in heavily affected forests, particularly on islands.

• 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, particularly on islands where the species occupies the lower strata of the forest.

• moderate level of threat to low elevation humid forest on the east coast through loss, modification and fragmentation of forest habitat to local agriculture.

• moderate level of threat to low and mid elevation humid forest habitat through repeated firing of adjacent savannah habitat, leading to loss and degradation of the forest edge.

• localised but moderate to high level of threat to mid elevation humid forest on the east coast through loss and modification of forest habitat to timber plantations and logging.

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

• localised but potentially intensive decline in area, extent and quality of closed forest habitat adjacent to urban development or intensive human settlement.

Conservation Status: Vulnerable.

The species is recorded from nine locations in the south of the main island (including several from the Ile des Pins) representing five disjunct sub-populations, and fourteen locations in the central and northern areas of the main island representing ~9 sub-populations. Although the species does not satisfy the criteria for a small distribution (area of occupancy >1000km2), it represents a special conservation case. The range of existing and potential high level threats identified above in combination with the specialised biology of the giant geckos in the genus Rhacodactylus, indicate Rhacodactylus lechianus satisfies the criteria to be categorised as Vulnerable. The sub-populations Ile des Pins could be placed at a higher level of conservation concern given the number and intensity of threats and the increased impact these threats have on insular sub-populations.

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