Specimens from the Sumbawanga region usually have a green yellow and black color pattern.

Neonates are a dark brown or gray, but with a bright yellow tail tip.

[6] Atheris rungweensis is known from scattered locations from south-western Tanzania to north-eastern Zambia and south to the Nyika Plateau in northern Malawi.

[3] Atheris rungweensis is usually found in low bushes along streams and at the edges of mountain forests at altitudes of 800–2,000 m (2,600–6,600 ft).

[4][7] Occasionally, it is encountered in moist savanna, woodland, and hill forest habitats.