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 are 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 

 transforai 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 wann, rainy nights. Calling normally takes place only when the 

 temperature is >50° F (Hammerson 1982). 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 is not known from ITNF lands; the nearest record is from Helena in 

 1988. Locally common in eastern Montana; there are large gaps in the known range. It 

 should be watched for at low elevations in prairie or shrub-steppe habitat on the HNF. Any 

 located on the HNF should be well-documented. 



Montana Natural Heritage Program rank: G5 S4? 



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