Head and neck: grey to black; head slightly distinct from neck; labials and throat yellow; 1 preocular; 3 postoculars; 7 upper labials, 3rd and 4th in contact with eye; 8 lower labials; able to hood and lift anterior part of the body when threatened;
Body: dorsal and ventral dark grey to black; skin beneath scales bright yellow, visible when snake is inflating its body; midbody scale rows 17 to 19; ventrals 165 to 178; subcaudals 42 to 50.