Pseudonaja mengdeni Wells & Wellington, 1985

Common Names & Size

Pseudonaja mengdeni, commonly known as Mengden's brown snake or western brown snake, reaches a maximum total length of 2 meters, with an average length of 1.2 meters. It has a slender body and a narrow head.

Dorsal Coloration & Patterning

This species shows high variation in color and patterning, ranging from light brown to nearly black, and occurs in two distinct forms: 'Orange with black head' and 'Pale head, grey nape'.

Ventral Coloration

The belly underside is most often cream, yellow, orange, or grey, and frequently marked with dark orange or grey blotches.

Head Scale Pattern

Scales on the head typically form a black V or W shaped pattern.

Confusion with Related Brown Snakes

Western brown snakes are often confused with related species: the Eastern brown snake has a pink mouth lining, while the Northern brown snake has a purplish or blue-black mouth lining, differing from P. mengdeni.

Distinctive Snout Scale

P. mengdeni has a distinctive large strap-like scale around the front of its snout.

Identification Requirements

Accurate species identification requires counting scales around the mid-body and along the lips.

Scale Count Characteristics

This species has 180 to 230 ventral scales, 45 to 70 subcaudals, a divided anal scale, and 17 or 19 rows of smooth mid-body scales.

Identification Risk Warning

Only experienced herpetologists should attempt this identification, because even a fang scratch from this species can be fatal.

Hybridisation as Identification Confound

Confusion between this and other species is often caused by possible hybridisation among species in the Pseudonaja genus.

Confusion with Other Snake Species

The western brown snake is also frequently confused with other Pseudonaja (brown snake) species and the black headed python Aspidites melanocephalus.

Geographic Distribution

This species is distributed from the coast of Western Australia through central Australia to north-western New South Wales and western Queensland. Its northern range limits are poorly defined. It is absent from the wetter regions of eastern Australia and south-western Western Australia.

Habitat Types

P. mengdeni occurs in all dry to arid areas, including woodlands, boree woodlands, sandhill woodlands, mallee woodlands, spinifex deserts, spinifex-covered dunefields, sandplains, stony plains, croplands, grasslands, and temperate sclerophyll forests.

Microhabitat Preferences

It is often found in fallen timber, dead trees, shrubs, native grasses, and ground cavities.

Reproduction

P. mengdeni is oviparous, and can lay more than 12 eggs per clutch.