The survival challenge of the lizard Phymaturus vociferator in central Chile

Abstract As ectotherms, high-elevation reptiles rely heavily on temperature fluctuations in their surroundings to maintain their physiological functions. If the rate of local adaptation does not keep up with the rise in temperature, these species are predicted to be especially vulnerable to global warming. A high-elevation endemic species from central Chile’s Mediterranean Andes, Phymaturus vociferator , lives in incredibly variable daily and seasonal thermal environments. We estimated standard thermal parameters related to body heating and developed correlational thermal models at two acclimation temperatures (20°C and 30°C) to determine their physiological vulnerability to climate change. Our results demonstrate that this species is a thermo-conformer, attributable to its ability to tolerate higher temperature regimes in the field as opposed to in the laboratory. As expected, the individuals demonstrated a higher threshold for temperature tolerance when acclimated to 20°C than when acclimated to 30°C. Additionally, we discovered that P. vociferator exhibits the widest eurythermal range among species in its genus. Although this result could help explain its potential physiological, this species’ capacity to adapt to global warming may be diminished by thermal physiological constraints.