Figure 1.

Two distantly related species, Mixcoatlus browni (a, b) and Crotalus intermedius (c, d), showing similar body size (maximum TL equals 51.5 and 57 centimeters, respectively), color pattern, and scale numbers (e.g., few scales on the head). This contrasts the distinction between C. intermedius (c, d) and its closer relative C. molossus (e, f), which lives in lowland, arid areas and has a larger body size (max TL 133 cm), different color pattern, and a greater number of scales. Photographs were taken by RCJ (b, d, e), Eric N. Smith (a, c), and Jonathan A. Campbell (f)