I just wanted to see what Ariel would look like as a pony. XD
Here she is. If you want to get technical, she's more along the lines of a hippocampus than a seapony but whatevs.
If you think about it, this would be kind of awkward for her dad. King Triton is essentially the Greek god Poseidon who, unlike his chariot iin the movie which was pulled by dolphins, actually rode a chariot pulled by hippocampi. So, uh, stop slacking and get back to work, Ariel. XD
(Oh and no cutie mark because it looked weird on her tail… Maybe she only gets it once she's transformed into a pony)