Is there a term to describe the impression of a insect that is formed if the same is crushed between the pages of the book. Or the impression of a mosquito that is killed in between our palms.
I would call this a pressing. Pressing flowers between the pages of books has been a traditional way of creating keepsakes. Here's instructions on how to press flowers in books.
You've just got a more morbid habit of creating pressed insects.
A relief. I'm being literal and punny.