You can check out this post about medieval images of knights fighting snails that appear in the edges of manuscripts that monks wrote. /u/sunagainstgold wrote the following quote:

"... the thing about the snails is, they're not always deployed the same way. Sometimes you have a knight jousting a BIG snail, sometimes you have a yelling angry snail on its own, sometimes you have a knight jousting a little snail, sometimes you have other animals jousting on top of snails.

Where we see jousting snails and other miscellany like this is decorative borders and random illustrations in luxury manuscripts. I tend to think of them a little bit like the cartoons and random drawings in the New Yorker--little illuminations that don't illustrate the text. There's a couple decades in the 1300s, for example, where adding strawberries to borders suddenly became A Thing--and then it stopped."