My interpretation of the bioluminescence on my Kronosaurus from Beasts of Bermuda, Lamia.
The bio pattern is the stripes from the Banded skin, and after 3000+ eggs I finally got her <3 she's now a chonky 2.2+ lady >:D

In game, the bio pattern passes over the eyes, and due to the shine of the bio it almost looks like she doesn't have eyes at all, so I took that and made her canon blind, having no eyes at all.

Living in the dark depths of the ocean, the bioluminescence's wispy bits and deep rumbly voice act as echolocation for her. Her favorite source of comfort in the vast expanse of the open sea is gently bumping against her brother Thresher, another bioluminescent Kronosaurus. Every once in a while they communicate by sending small rumbles of acknowledgement of the other's presence, just to let the other know they are still there.