Combined a bunch of things together and got this evolution line. Obapiscetilus -> Palinucanis -> Anomalocampus. I originally intended it to have an outer shell with ammonite-like suture lines in red, with a black body, but that may be too detailed for turning into pixels so I am leaving the colour design empty and free to have any colour interpretation added. Maybe something rainbow would work as the design is partly inspired by long gone sea animals whose remains sometimes fossilize in rainbow opal colours.
Obapiscetilus = Opabinia + Pisces + Nautilus
Palinucanis = Palinurus elephas (Lobster) + Canis
Anomalocampus = Anomalocaris + Hippocampus.
Concept:

Descriptions for all or either one that could be chosen from them: