Great Basin Spadefoot
The great basin spadefoot has much smoother and less warty skin than other toads.
About This Species
The great basin spadefoot prefers arid environs and can be found in pinyon-juniper woodlands and in sagebrush fields.
More Information:
Physical Characteristics
Pupil vertically elongated (like a cat) in bright light; a single hard, wedge-shaped spade on each hind foot; glandular lump directly between eyes (lump is not as far forward as in the plains spadefoot); head and body length usually less than 6.5 cm (2.6 inches), adults average about 2.0-2.4 inches long.
Mature Male
Dark patches on inner three toes of front feet during breeding season; expanded vocal sac slightly two-lobed.
Range
Northwestern and west-central Colorado. Locally common but seldom seen.
Habitat
Breeds in pools and stock ponds filled by heavy rains or flooding in basins and rocky canyons, in areas with sagebrush, semidesert shrubland, or pinyon-juniper woodland.
Reproduction
Breeding Call
A nasal “waaa” (rhymes with “laugh”).
Larvae
Upper side brown to blackish, large individuals appearing relatively pale; fins mainly clear or may have sparse dark scrawls or fine dark markings except on basal part of lower fin; eyes close together on top of head; both jaws serrated; lower jaw not striated; carnivore morph has a broadened head, a cusp on the upper jaw, and a notch in the lower jaw; usually 3-4 rows of tiny teeth on upper lip, 4 rows on lower lip; large larvae often 5–6 cm (2.0-2.4 inches) long, up to at least 8.5 cm (3.4 inches) in Colorado.
Eggs
Deposited in small strings, sheets, or clusters up to about 2 cm (0.8 inches) in diameter, generally 10–40 eggs per cluster; attached to submerged plants or other objects.
Life History
Spends most of its life buried in the soil. Emerges to breed after heavy rains in spring or summer. Larvae develop quickly and metamorphose into small toads usually within a few weeks.