>>48241023>>48241030>>48241035>>48241042Possibly Huntail and Gorebyss look for the empty shell of a Shellder and put their egg there, or if you want to be more sinister put the egg in a live Shellder and when the "baby fish" is born, devour the shellder and modify the shell that will serve as its refuge. until evolve.
Another interesting detail is that as the Clampearl evolves its shell becomes part of its body, like a breastplate in Gorebyss and like a headdress-fin on Huntail's head.
This would also explain the symbiotic relationship Shellder-Slowpoke, where Shellder gains motility on land and protection from predators.