Thigmotaxis is not shown by

Ascaris do not show thigmotaxis. Amoeba shows thigmotaxis. On coming in contact with a solid object Amoeba generally avoid it by moving in a different direction by forming pseudopodia. Hydra is known to respond to a variety of stimuli, both external and internal. On contact with a solid object other than a prey, the whole body usually contracts rather rapidly. On contact with a hard solid object Paramecium induces avoiding response.