Selection of environmental temperature by the yellow scorpion Tityus serrulatus Lutz & Mello, 1922 (Scorpiones, Buthidae)

Hoshino, K.T. V. Moura, A.M. G. De Paula, H.

The preferred temperature of the yellow scorpion Tityus serrulatus was investigated since its dispersion is a matter of concern. Adult T. serrulatus, weighing 1.24 + 0.20 g (mean + sd) and with a standard length of 59.3 + 2.5 mm, were used. A metallic corridor (120 cm long, 5 cm large and 10 cm high) with thermal gradient ranging from 0°C to 40°C was used. Tityus serrulatus chose and stayed in temperatures ranging from 14°C to 38°C when safe conditions were offered (dark and thigmotactic stimuli). The number of animals that remained in the 11°C-20°C, 21°C-30°C, and 31°C-40°C temperature zones were 8, 8, and 9, respectively. The chi-square test (degree of freedom = 2) showed that differences were not significant (p>0.05). Some animals moved to lower temperature areas (less than 8°C) when the corridor was completely illuminated and thigmotactic stimuli were absent, which led the animals to present a torpor state. It is concluded that T. serrulatus does not select a specific environmental temperature. Associated with the capacity of temporally surviving at low temperatures, this species seems to be highly adaptable to different thermal zones.

1. scorpion
2. Tityus serrulatus
3. thermal gradient
4. zoogeography
5. temperature