Varanus pilbarensis

Maryan, Brad, Oliver, Paul M., Fitch, Alison J. & O’Connell, Morgan, 2014, Molecular and morphological assessment of Varanus pilbarensis (Squamata: Varanidae), with a description of a new species from the southern Pilbara, Western Australia, Zootaxa 3768 (2), pp. 139-158 : 144-145

Varanus pilbarensis species-group

Diagnosis. Differs from all other Australian Varanus in the combination of small size (adult SVL up to 180 mm); slender build; tail long (170–210% length of body) and thin, circular in cross section at midpoint, midbody scales 118–128; dorsal and lateral scales weakly keeled, enlarged keeled ventrolateral scales on each side of and posterior to vent in 4–6 rows, scales on top of head smooth; supraoculars gradually merging with the larger interoculars; nostrils high and oriented dorsolaterally, and reddish base colouration of the dorsal and lateral surfaces of head and body.

Comparisons with other species. The diagnosis above readily differentiates the V. pilbarensis species-group from all congeners, however a small number of species warrant additional comparison: Varanus tristis also occurs in the Pilbara region but is larger (maximum SVL up to 280 mm v. 180 mm), has more midbody scales (between 119–152 v. 118–128), a less depressed head with a comparatively shorter snout, and a larger and more spinose cloacal scale cluster ( Storr et al. 1983). Within the Pilbara, V. pilbarensis is also strictly saxicolous and has a reddish ground colour over most of the dorsum, whereas V. tristis is largely arboreal and grey, dark brown to black over the dorsum. Varanus glauerti from the Kimberley is a saxicolous species similar in appearance to V. pilbarensis (depressed body, long tail and dorsal ocelli); however, V. glauerti attains a larger size (maximum SVL up to 227 mm v. 180 mm), has more midbody scales (between 122–151 v. 118–128) and a proportionally longer tail (between 183–268% of SVL v. 170–211%).

All subsequent morphological comparisons will involve only the two species in the Varanus pilbarensis species-group.