Plains Spadefoot (Scaphiopus [=Spea] bomhifrom) 



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 vvart>' 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 are attached to underwater plants or 

 debris. Tadpoles are mottled soot>' 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. Harrmierson 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 heaxT 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). During dry 

 periods, adult spadefoots may remain inactive and underground for periods of up to several 

 years in length. 



Status: The Plains Spadefoot is not known from the study area; the nearest records are from 

 Cascade County about 20-30 miles west of the Highwood Mountains. WNW of the Little 

 Belt Mountains, and in Great Falls. Locally common in eastern Montana. There are large 

 gaps in the known range probably due to the long time periods this species may spend 

 underground, especially during droughts. It should be watched for at low elevations in prairie 

 or shrub-steppe habitat on the study area; any located should be reported. 



Montana Natural Heritage Program rank: G5 S4? 



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