The three species were officially separated in 1991 in a publication from P. A. Rawlinson, detailing key differences in appearance, distribution and behaviour between each type.

It is expected for the males to grow to a larger size than the females, but the pygmy copperhead's ratio is more marked than most other snake species.

[16] The abdominal area is cream to light-grey in colouration, with varying intensities of red along the edges before transitioning to the brown-grey backside.

[1] The limited area is characteristically moist, with an average yearly rainfall of 600–800 mm (23.6–31.5 in) and milder summer temperatures, 23–25 °C (73.4–77.0 °F).

[5] They are found living in concentrated numbers[15] near streams, in swamps, marshland and open sclerophyll woodlands and forests.

[17] Combat between males signifies sexual maturity in snakes, but it has not been observed in pygmy copperheads, despite the lowland and highland species exhibiting at two years of age.

[5] Being carnivorous, the pygmy copperhead's diet consists of smaller ectotherms, most commonly including small lizards, frogs and tadpoles.

[6] The pygmy copperhead’s venom is classed as strongly neurotoxic, with toxicity similar to that of the Indian cobra.

[5] Antivenom developed through the tiger snake is unable to completely neutralise the neurotoxicity of the whole venom, nor a modified version in research lab trials.