Northern spadefoot toad

Notaden melanoscaphus

TAXONOMY

Notaden melanoscaphus Hosmer, 1962, Borroloola, Northern Territory, Australia.

OTHER COMMON NAMES

French: Pied-en-bêche du nord.

PHYSICAL CHARACTERISTICS

This moderate-size, rotund species has short limbs and a short snout. The males are 1.3–1.9 in (34–48 mm), and the females are 1.8–1.9 in (45–49 mm). The dorsum is gray or olive brown, with large, dark, symmetrical blotches. The dorsum is warty, and the warts commonly are tipped with white. Juveniles typically have bright yellow, red, and black spots. The inner metatarsal tubercle is black and keratinized.

DISTRIBUTION

The species is widespread in eastern and northern Kimberley, Western Australia, across to Townsville, Queensland, Australia.

HABITAT

The frog is found in flooded grassland after torrential rains.

BEHAVIOR

This burrowing species exudes a sticky, yellow-orange, gluelike substance when disturbed; the exudate hardens quickly and is difficult to remove. It does not appear to be toxic to other frogs. These frogs run rather than hop; at night they can be mistaken for small rodents.

FEEDING ECOLOGY AND DIET

The mouth is small, and, hence, these frogs are restricted in their diet to small arthropods. They flick the tongue rather than bite at prey.

REPRODUCTIVE BIOLOGY

Males inflate the entire body while lying in shallow water and call, "whoop, whoop, whoop." If disturbed, they deflate, sink, and remain silent until the threat has passed. Males grasp females in inguinal amplexus, and eggs are laid as a surface film that sinks as the larvae hatch. The tadpoles seem to be filter feeders rather than grazers.

CONSERVATION STATUS

Not threatened. The species is secure across its range.

SIGNIFICANCE TO HUMANS

None known.