Rothschild's rock-wallaby (Petrogale rothschildi) – sometimes known as the Roebourne rock-wallaby, is a species of macropod found in Western Australia, in the Pilbara district and the Dampier Archipelago. It is not currently considered to be threatened, but is at risk from the red fox (Vulpes vulpes). Rothschild's rock-wallaby is one of the largest rock-wallabies. It is predominantly golden-brown in colour with a greyish wash down its neck, which often has a purple appearance. It is mainly a nocturnal grass-eater usually found around rocky ground. Taxonomy Petrogale rothschildi was first described by Oldfield Thomas in 1904, describing a skin provided by J. T. Tunney's collection from the Northwest of Australia. Tunney's specimen was a female's skin, without a skull, collected in July 1901 at Cossack River. Thomas saw an affinity with what was termed the Petrogale pencillatus-lateralis group, but distinguished enough characteristics to propose a new species of the rock wallabies. The author honoured a patron of Tunney's expeditions in the naming of the species, Walter Rothschild, whose special interest in Macropodidae was also noted. Description Described as one of the most appealing species of Petrogale, the rock wallabies, it is also one of the largest of the genus. The fur colour at the upperside is a golden shade of brown, becoming greyish at the shoulders and rear of the neck. The top of the head and muzzle is dark brown, contrasting the paler grey-buff at the lower muzzle that extends below the eyes to the upper surface of the ear. The pelage sometimes has a purplish hue, most evident at the shoulder and head. The head and body length combined is 470–600 millimetres, with a long tail recorded as 550–700 mm; the colour of the tail becomes dark brown for around a third of its length. The length of the ear from its point to the base is 56 mm. The weight range of Petrogale rothschildi is 3.7–6.6 kilograms. The population found at the islands of the Dampier Archipelago are smaller than those on the mainland, the weight range is from 2.6 to 3.5 kilograms. Behaviour and habitat The species seeks shelter during the day in the cooler temperatures provided by the crevices and caves of its favoured habitat. They are highly secretive in their behaviour and use the rocky terrain to remain hidden or inaccessible to predators. Rothchild's rock-wallaby occurs at hummocks of vegetation covering scree slopes, around boulder