Semicossyphus pulcher is a species close to my heart. I spent two years diving with California Sheephead while teaching at Catalina Island Marine Institute. The concept of sequential hermaphroditism (gender change) always blew students' minds so it seemed a great topic for an illustration. Also, these fish are gorgeous.
First, a concept sketch.
I started with the text/illustrations I knew I wanted to include, then improved the design and settled on the bottom image. I chose a square format so it would look good on Instagram (shameless, right?)