The longest specimen recorded was 2.44 m. The head and upperparts are dull or glossy black, or occasionally dark brown, and underparts are blue-grey or gunmetal grey.

[6] It just enters Australian territory as it occurs on Boigu and Saibai Islands in far northern Torres Strait off the New Guinea coast.

Unlike those of other black snakes,[7] the venom is predominantly neurotoxic in its effects, with muscle weakness and paralysis ensuing within 2 to 21 hours of being bitten.

[10] Although widely feared in Papua New Guinea's Central Province, it is responsible for only a small minority of snakebites, eclipsed by the more dangerous taipan.

[6] The first to extract Papuan black snake venom for scientific purposes was Australian herpetologist Ken Slater in the mid-1950s.

It was first given to a young male bite victim in New Guinea in 1959, who became the first documented survivor of a Papuan black snake attack.