How to Identify Millard's Hump-Nosed Pit Viper (Identification Guide)

Key identifying features

Millard's Hump-Nosed Pit Viper is a small terrestrial pit viper recognized by its distinctively upturned, hump-like snout, a feature shared with a small group of related "hump-nosed" pit vipers in South Asia. It has the broad triangular head, heat-sensing pits, and vertical pupils typical of pit vipers, but its snout shape sets it apart from most other regional species.

Coloration & pattern

The body coloration is generally cryptic, consisting of grayish, brownish, or reddish-brown tones overlaid with a pattern of darker blotches, triangles, or irregular markings along the back, which help the snake blend into leaf litter on the forest floor. This earthy patterning contrasts with the bright greens of many arboreal pit vipers, reflecting this species' more terrestrial habits. The belly is typically pale, often cream or light gray, sometimes with scattered darker flecking.

Head, eyes & scales

The most notable feature is the upturned, somewhat pointed or hump-shaped snout, giving the face a distinctive profile compared to the more rounded snouts of most other pit vipers. The head is otherwise broad and triangular, clearly wider than the neck, with a heat-sensing pit between each eye and nostril. Eyes show vertical pupils. The dorsal scales are strongly keeled, giving the body a notably rough, almost bristly texture.

Size & body shape

This is a small pit viper, with adults typically reaching only about 30 to 50 centimeters in total length. The body is relatively stout for its size rather than slender, consistent with a terrestrial, leaf-litter-dwelling lifestyle rather than an arboreal one.

Range & habitat where you'll see it

This species occurs in parts of South Asia, generally in forested habitats, where it lives primarily on the forest floor among leaf litter, fallen logs, and low vegetation rather than in the tree canopy. It is most active at night and relies heavily on camouflage, often remaining still and difficult to spot against the forest floor.

How to tell it apart from look-alikes

The upturned, hump-shaped snout is the single most useful field mark for distinguishing this species from other pit vipers in its range, since most regional pit vipers have a more evenly rounded snout profile. Its terrestrial, leaf-litter-camouflaged coloration further distinguishes it from the bright green arboreal pit vipers found in the same general region. As with all pit vipers, the broad triangular head, vertical pupils, and heat-sensing facial pits confirm its identity as a venomous pit viper rather than a harmless ground-dwelling colubrid snake.