Try checking it at night with a light. A lot of leaf munchers only come out under cover of dark.

nothing seems to eat mine, but maybe snails or slugs? I do use bait. The leaves are poisonous by the way.

Tropical_thought:
Philodendron leaves are poisonous? I am in the process of growing Taro Roots , are these in the same family and poisonous too??

Most aroids are toxic, some far more than others. Taros included. Cultivated taros have been bred over the centuries for lower levels of toxicity, but most still do have some. Cooking destroys the toxins, something that humans worked out long long ago. But it's a long and thorough process. Don't try nibbling them raw, but otherwise they're quite okay done properly. They've been the staple food of many people for a long time.