Sex identification in the eastern blue-tongued lizard (Tiliqua scincoides White, ex Shaw, 1790) using morphometrics.

Abstract

OBJECTIVE: To establish a repeatable, well-tolerated, non-invasive technique for sex identification in eastern blue-tongued lizards (Tiliqua scincoides). METHODS: Measurements were obtained from 69 free living eastern blue-tongued lizards presented for treatment that were either deceased on arrival or subsequently euthanased on welfare grounds. Weight, head width (H), snout vent length (SVL) and trunk length (T) were recorded. Ratios for head width to snout vent length (H/SVL%) and head width to trunk length (H/T%) were calculated. Sex was identified at necropsy. RESULTS: Evidence of sexual dimorphism in this population was shown. However, the degree of difference was subtle, requiring the use of ratios in order to refine the technique. Ratios of H/SVL% and H/T% showed significant predictability with respect to sex identification in both adult and sub-adult lizards. CONCLUSION: This study established a protocol for a repeatable, non-invasive technique for sex identification in the eastern blue-tongued lizard (Tiliqua scincoides) and provides a normal reference range.