textless:

There are so many of these tiny toads along parts of the San Pedro River that you have to walk carefully.  They hide in the grass, bask on the mud, and hunt event tinier insects on the water weeds. 

They are Red-Spotted Toads, fairly common across most of Arizona (https://www.nps.gov/grca/learn/nature/red-spotted_toad.htm).  These were found in May, 2018.