English zoologist Hampton Wildman Parker described the speckled brown snake as Demansia guttata in 1926 from a specimen collected in Winton, Queensland.

[1] The brown snakes were moved to Pseudonaja by Australian naturalist Eric Worrell in the early 1960s on the basis of skull morphology, and reinforced by American herpetologist Samuel Booker McDowell in 1967 on the basis of the muscles of the venom glands.

[3] A 2005 analysis using mitochondrial DNA found that the speckled brown snake was an early offshoot of the genus, with the taipans as more distantly related.

[7] The speckled brown snake occurs in the Channel Country, Mitchell Grass Downs, and Mount Isa Inlier[1] in Northern Territory, Queensland, and South Australia.

[1][2] Frogs and lizards make up a large proportion of its diet, though it also eats small birds and mammals.