Spotted dolphin.

Trying my hand(after quite some time) on freehand dolphins

Fun fact: Cetaceans were one of the first animals I did a major (art) project on in about the 3rd grade or so. I could even spelled cetacean and knew what the word meant at that young, though I miss pronounced it as See-ta-seen rather than See-Tay-shin.
I also knew about Mysticeti and (my more favorite) Odontoceti.
It was for a small educational popup book I made

My interest was mostly spurred on by Ecco the Dolphin, naturally.

I had also read, about seven or so volumes Ocean World of Jacques Cousteau at about the same time, that I found in a thrift store.