Thalassophobia is a morbid fear of the sea that has led to some interesting image memes. Threads with images of giant sea creatures threatening tiny humans are not uncommon these days.

Magnathorax:

This creature was made up with other myths about the Bermuda Triangle.

Giant Arthropod:

Giant Coelacanth:

Lovecraftian Horror Monster:

Do Not Want:

Megalodon:

I completely understand why this meme is big. Whenever I'm in the ocean I imagine gigantic creatures like this below me.

As far as I can tell this meme is limited to 4chan, but I could be wrong.

Related posts: Cephalopod Memes