| Plains Spadefoot Toad | |
|---|---|
| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Amphibia |
| Order: | Anura |
| Suborder: | Mesobatrachia |
| Family: | Scaphiopodidae |
| Genus: | Spea |
| Species: | S. bombifrons |
| Binomial name | |
| Spea bombifrons (Cope, 1863) |
|
| Synonyms | |
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.
The Plains Spadefoot Toad generally grows from 1.5 to 2.5 inches in length, has a round body, with relatively short legs. These toads are usually a tanish to dark brownish color with visible orange spots. They are one of the easiest toads to recognize in their region because of their appearance looking more like a frog. Sometimes they have light striping on their back.
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 metamorphose 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.[1] Character displacement has also been examined in ponds where Spea bombifrons and Spea multiplicata occur together. Researchers found that reproductive and ecological competition between the two species likely causes selection for smaller and less reproductively successful individuals of Spea multiplicata. [2]