Pliny's Natural history
Ctesias writeth …
they are called Sciopodes
because in the hottest Season
they lie along on their back on the ground, and defend themselves with the shadow of their feet.
The sun is the breadth of a man's foot.
Gaius Plinius Secundus, Historiae Naturalis
Ctesias scribit …
quod in maiore aestu
humi iacentes resupini umbra se pedum protegant.