Seeking gardening help
@adeptomega I'm not seeing anything in a google search and a couple of botanical sites that look like that. Is it only the one leaf? Do the others look normal? If so, that may be "something bit this" and the moisture got in." Trimming the one leaf is probably enough. If you look underneath, and you don't see any eggs, white or yellow spots on the leaves, or weak stems, I think we're safe. If you see anything else, let me know; we can look that up.
Seeking gardening help
@literorrery @adeptomega the advice I got from my mother was:
"Trim the leaf. Throw it away.
I don't know your local pests but there should be a local county agricultural agency that can receive pics and tell you what might be in your vicinity. They should have free consults via phone and email.
Otherwise it looks really healthy!"