@Cyborg_pony
 
Sea Foam is a species named “Fishy-Tail Pony”
 
Feel free to look it up on deviantart
 
~ iPandacakes

@Cyborg_pony
 
According to artist:
 
Fish (Creature) in Tail: Dwarf Cuttlefish named “Sepia” (Genus of the cuttlefish family)  
Short Bio: Sea Foam learned how to manipulate the water around her tail at the beach.  
She always loved the ocean and dreamed of finding a sea fish to inhabit her tail one day.  
To her luck, one day after a storm, a mini cuttlefish was swept into a tide pool near her routine pathwalk down the beach.  
She immediately fell in love with this cute, tiny cephalopod; and took her in instead of a fish. She named her “Sepia” in honor of her Genus Species name, “Sepia bandensis”

So she’s a cuttlefish turned into a pony?