>>31795108But Dewpider's says that it crawls onto land in search of food, although I guess it doesn't specifically say prey....
On a separate note I don't think it's a stretch to propose that Cutiefly are probably Araquanid's main source of food. Spiders are usually depicted eating flies, and Cutiefly is tied for being the smallest pokémon in existence -- one of the few feasibly small enough to drown in the bubble.