Locomotory Capacities, Oxygen Consumption, and the Cost of Locomotion of the Shingle-Back Lizard (Trachydosaurus rugosus)

Trachydosaurus rugosus is a large, slow-moving Australian skink. The maximal sprint velocity of this species averages only 2.7 km/h and is apparently limited by short limbs that have relatively little muscle mass. Standard metabolic rate at 35 C is 0.073 ± 0.009 ml O₂/(g·h), and the maximal rate of O₂ consumption is 0.722 ± 0.019 ml O₂/(g·h). The maximal aerobic speed is 0.67 km/h, and endurance at 1.0 km/h is 23 ± 7 min. The net cost of locomotion (CN) is 0.921 ml O₂/(g·km) (95% confidence limit [C.L.]: 1. 133, 0.709). This value is tabulated together with all other data available for lizards, and a new allometric equation describing net cost of locomotion as a function of body mass is presented. For all lizards, CN (ml O₂/(g·km) = 4.22 (body mass, g)−0.282. The locomotory and energetic capacities of Trachydosaurus describe an unusually slow lizard with limited stamina.