I'd be curious to learn how this was made, was it rendered out in black/white from a 3D animation? The dithering seems to be too sporadic and the animation too centered for it to be drawn frame to frame.
Either way, it's a neat visual for sure, potentially useful after a catch in a fishing game.
It seems the original image is no longer a file for download, I tried opening the .gif in Aseprite and got a more compressed image, lacking most of the antennae.