Adults of
L. ahaetulla may attain a total length of , which includes a tail long.
Dorsally,
L. ahaetulla is bright green, golden, or bronzy. The keels of the
dorsal scales are black or dark brown. The head shields and the dorsal scales may be edged with black. On each side of the head is a black streak which passes through the eye. The upper lip and the belly are white or yellow. The species was thought to be non-venomous, but it is mildly venomous with localized pain, swelling and a feeling of "pins and needles" being the symptoms of envenomation. Symptoms disappear after a few hours. The head is elongated and distinct from the neck. The eye is large with a round pupil. The body is slender, and the tail is long. The dorsal scales are arranged in 15 rows at mid-body and are strongly keeled except in the first row on each side (the row adjacent to the
ventrals), where they are smooth. They are also smooth on the neck and tail. The ventrals, which number 151-167, are strongly angulate at the sides. The
anal plate is divided. The
subcaudals number 140-173, and are divided. The
loreal scale is absent, and the
prefrontals extend through the loreal region to contact
the upper labials. There are usually 2
postoculars, and the
temporals are 1 + 2. There are 8-9 upper labials, of which the 4th & 5th (or 5th & 6th) enter the eye. The anterior
chin shields are shorter than the posterior chin shields. ==Diet==