This condition makes it much more difficult to identify the species from the photos. There are three spadefoot species in this area: Spea bombifrons, Spea multiplicata, and Scaphiopus couchii. All three have very similar body shapes, and they overlap in size. S. couchii gets bigger than the other two, but this one was of a size where it could have been a medium-sized S. couchii or a full-sized S. bombifrons or S. multiplicata. The shape of the hardened "spades" on the rear legs would distinguish Spea from Scaphiopus, but I didn't know that at the time and so didn't check for that.
The "boss" between the eyes that I mentioned earlier is present in S. bombifrons but not in the other two species. To me and some others who have looked at these photos, that boss appears to be present here (especially in the first photo), but it's not completely clear. So I'm tentatively calling this S. bombifrons. Please send me mail if you have an opinion on the matter!
- Brennan, T. C. and Holycross, A. T. 2006. A Field Guide to Amphibians and Reptiles in Arizona
- Crother, B. I. (ed.) 2017. Scientific and Standard English Names of Amphibians and Reptiles of North America North of Mexico, with Comments Regarding Confidence in Our Understanding, Eighth Edition
- Elliott, L., Gerhardt, C. and Davidson, C. 2009. The Frogs and Toads of North America
- Stebbins, R. C. 2003. Peterson Field Guide to Western Reptiles and Amphibians, Third Edition