Plains Spadefoot
(Spea bombifrons)


The Plains Spadefoot (Scaphiopus bombifrons) is a member of the North American family Pelobatidae that occurs in the dry grasslands from southern Canada down into northern Mexico.  Like other Spadefeet (Spadefoots?), this species spends much of its life underground and only comes to the surface after periods of rainfall.


The range of this species in the state of Texas is rather odd.  There is a relatively contiguous population that extends across the southern part of the plains states into the panhandle of Texas and the grasslands of western Texas.   But in South Texas there is a population in the sandy grasslands of the Tamaulipan Biotic Province.  This population appears to be isolated from the main population and is very patchily distributed within that South Texas range.  Many areas that this population formerly occupied are now heavily disturbed by agricultural practices.

The scientific name bombifrons is a reference to the bony "boss" on the skull between the eyes that distinguishes this species from similar species.



Plains Spadefeet call from flooded playas and other temporary ponds during seasonal summer rains.  They appear as if by magic after rains come to the dry grasslands, appearing from under the soil, moving to the flooded areas to breed quickly.  Their tadpoles mature very rapidly and metamorphose into tiny "toadlets" which move across the landscape in huge numbers feeding and eventually burrowing into the soil again.


I recorded this individual in this flooded agricultural field in Garza County, Texas after some heavy summer rains.  It was recorded at 10:30pm.



The road near this flooded field was covered in hundreds of small "toadlets" of this and other species.  Many were less than an inch long.



I only heard a single spadefoot calling that night, probably because they had bred earlier in the year when there were heavy rains.


The call is a short dyspeptic groan.  It is reminiscent of the longer groan produced by the related Couch's Spadefoot.


I was finally able to get a decent recording of a chorus of these spadefeet in South Texas in March, 2107 after some heavy spring rains. They were calling amidst a heavy chorus of Texas Toads (Anaxyrus speciosus). I have filtered out the higher Texas Toad calls.


© Chris Harrison 2015 & 2017

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