|Photo by Ned Harris 9/11/2015
|Photo by Ned Harris 9/16/2015
From Reptiles of AZ (the link above):
Couch’s spadefoots remain buried in the soil for 8-10 months and then emerge at the onset of the summer monsoons. This species is frequently encountered on roads during warm, humid summer nights. Adults are nocturnal, but metamorphs [Anne notes: like this little one] are often active by day.