Allometric relationships between cutaneous surface area and body mass in anuran amphibians

Several allometric relationships exist in the literature describing the relationship between surface area (AS) and body mass (MB) for different taxa of Anura and these are frequently used in physiological studies. Here, we gathered literature data of AS (cm2) and MB (g), added new original data, and allometric relationships between AS and MB were evaluated using linear and phylogenetic generalized least-square (PGLS) regressions. Data from 453 specimens from 44 species were included. Intraspecific allometric relations between AS and MB were determined for 18 species, with ten of those showing regressions not significantly different from the respective family regression; four species showing a significantly different y-intercept; and three species showing a significantly different slope. Only the families Bufonidae, Ranidae, and Hylidae were represented by several species (9, 11, and 12, respectively) and with larger specimens’ numbers (54, 215, and 127, respectively). These three families exhibited significantly different OLS linear regressions on log10-transformed data, with Hylidae showing the steepest (0.7735 ± 0.0110), Bufonidae an intermediate (0.6772 ± 0.0220), and Ranidae the lowest slope (0.6091 ± 0.0114). The relationship between AS and MB for Anura could be described by the linear regression AS =  9.8537 MB0.6745or by the PGLS regression AS = 8.7498 MB0.685.