Plains Spadefoot {Scaphiopus [=Spea] bombifrons) 



Description: Adults are colored gray or brown with darker mottling on the back and a white 

 belly. Some individuals have indistinct longitudinal streaking. The pupils of the Plains 

 Spadefoot are vertically elliptical and there is a high, hard lump between the eyes. Its skin is 

 less warty than true toads. The adult has a single tubercle on the hind feet and has a body 

 length of less than 2.5". 



Eggs and Tadpoles: Oval egg masses of 10-250 eggs a-c attached to underwater plants or 

 debris. Tadpoles are mottled sooty and olive-yellow above and paler below with gold 

 metallic flecking over all; iris is gold. 



Similar species: Other Montana frogs and toads have round or horizontally elliptical pupils. 



Habitat and Habits: Adults are found in grassland and sagebrush areas, particularly in areas with 

 sandy or loose soil (Wheeler and Wheeler 1966, Hammerson 1982a, Baxter and Stone 1985). 

 Except during breeding, they are seldom found in the water. They are primarily nocturnal 

 and emerge from their burrows only following heavy rains. They breed in shallow temporary 

 pools usually following heavy spring or summer rains (Hammerson 1982a). Males call 

 loudly, with groups being heard for up to a mile. Eggs hatch after 2-3 days and tadpoles 

 transform in 6-10 weeks (Wheeler and Wheeler 1966, Hammerson 1982a). 



Surveying: Adults may be easily found by using their calls for identification when breeding at 

 night or by "road hunting" on warm, rainy nights. Calling normally takes place only when 

 the temperature is >50° F (Hammerson 1982a). Tadpoles are seen in ponds during the day 

 and can be sampled with a dipnet. Surveying is complicated by the long time periods which 

 this species spends underground, especially during droughts. 



Status: The Plains Spadefoot was found at a single location in the Ekalaka Hills dung our 1994 

 survey; there is also an historic location from the Long Pines (Appendix 4). It is locally 

 common in eastern Montana, but there are large gaps in the known range. It should be 

 watched for in prairie or shrub-steppe habitat on the Sioux-CNF. Any located on the Sioux- 

 CNF should be well-documented. 



Montana Natural Heritage Program rank: G5 S4? 



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