5363 x 3588 px | 45,4 x 30,4 cm | 17,9 x 12 inches | 300dpi
Data acquisizione:
1995
Altre informazioni:
The Plains Spadefoot Toad (Spea bombifrons) is a species of spadefoot toad which ranges from southwestern Canada, throughout the Great Plains of the western United States, and into northern Mexico. Like other species of spadefoot toad, they get their name from a spade-like projection on their hind legs which allows them to dig into sandy soils. Plains Spadefoot Toads are nocturnal, and secretive. They spend most of the dryer seasons buried in the soil in estivation, typically only emerging during spring and fall rains. Breeding takes place in temporary pools of water left by rainfall, which requires the tadpoles to metamorphosize quickly, before the water dries up. Eggs, laid in clutches numbering from 10-250, often hatch within 48 hours of being laid, and the larvae can change into toadlets in as little as two weeks. The tadpoles exhibit phenotypic plasticity, with some tadpoles changing from an omnivorous morphology into a cannibalistic carnivorous morph with oversized jaw muscles and a pronged beak. A recent study has shown that in some cases female spadefoot toads will choose to mate with Spea multiplicata rather than with males of their own species, if the resulting hybrid tadpole would have higher chances of survival.