The big-footed thorius grows to just over 50 mm long. It has long limbs with large, broad hands and feet, and is found in both terrestrial and arboreal habitats. Within its pine-oak cloud forest habitat, it has been seen both on the ground under rocks and leaf litter and inside piles of wood chips, and between the leaves of bromeliads growing on trees. Its habitat is threatened by human encroachment, in the form of logging, livestock, and subsistence agriculture.