wiki thumbnail problem

Lord Bowser

Banned User
so for some reason it seems like File:Pine T. Jr..PNG is having trouble rendering as a thumbnail at certain sizes. this can be seen on my sandbox (User:Lord Bowser/sandbox), where i tried to thumbnail it at multiple different sizes.

could someone explain why this is happening, and how to fix it? i'll need it as soon as possible for a shroom section. my initial thought was that the double period in the image name was the culprit, but i don't want to move it without knowing for sure if that's it.
Yes, it's the period. I have moved the file and will replace the link on the article.