The Silverstone’s poison frog’s fingers are flattened and have small, expanded discs at the tips with no webbing between the digits.
The Silverstone’s poison frog’s fingers are appressed and flattened and have small, expanded discs at their tips.
The relative length of the appressed fingers is 3>4≥1≥2, each terminating in slightly expanded disc. If measured from the base, finger 1 is distinctly longer than fingers 2 and 4, but when appressed their discs overlap and the three are nearly equal. The disc of third finger is 1.20-1.56 times wider than distal end of the adjacent phalanx, with no appreciable sexual dimorphism.
A large, circular to elliptical tubercle is located on the median base of palm, and a small elliptical one (=inner metacarpal tubercle, but sometimes indistinct) is on the base of the first finger. These tubercles are low, with rounded surfaces. Some individuals have a suggestion of small, low, and poorly defined tubercles on the palm distad from the large one. One or two subarticular tubercles are on the fingers (one each on fingers 1 and 2, two each on fingers 3 and 4). The subarticular tubercles are somewhat protuberant in lateral profile. A few specimens have a keel-like ridge extending from the outer side of the large palmar tubercle to the proximal subarticular tubercle on finger 4.
There is no webbing between the digits of either the hands or feet. They also lack distinct interarticular tubercles or lateral fringe.