That looks more like mechanical damage, say from hail or heavy rain to me. It also may be from leaf-cutter ants if you have those where you are.
Please fill in your profile to include your location? This helps a lot in answering questions. Just a zone doesn't help, we need to know a city/state/country please.
My lotus are currently dormant but as they were winding down at the end of the season, they got marks on the leaves like that.
