Abstract
Snakes in the Australo-Papuan elapid genus Oxyuranus are considered to be the most venomous species in the world. A recent expedition to the central ranges of Western Australia discovered a third species, which is described here from the only known specimen. Molecular genetic analyses using mitochondrial nucleotide sequences places the new species as the sister lineage of the two described Oxyuranus species, with all three species united by a long branch that also separates them from the nearest of the brown snakes species (Pseudonaja) to which the taipans are close relatives. Morphologically, the new species shares with the other Oxyuranus an undivided anal scale, high midbody scale row (21) and ventral scale (250) counts, but differs in having a single primary temporal scale and fewer lower labials (six). Maximum body size and venom potency are unknown. The discovery of a third species of taipan in the remote central ranges of Australia underlines the paucity of collecting from this region.
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