>>34586101It's more of how they live.
Scale insects are slow bugs that often attach themselves to stems and branches to suck on nutrients. The females will literally latch on to things for their entire lives in some cases, never moving again. Their main defense mechanism is these these hard, rock like shells they grow as they need to stay in the same place for feeding for a extensive period of time and need them so they don't become prey
Shuckle seems to be inspired by a lot of things but these seem to be the actual bugs it was inspired by.