>>13615039They're based on the Nazca lines, huge pictures in the desert in Peru. Sigilyph is specifically the hummingbird picture. It's also based on the kachina, a western Pueblo spirit that is the personification of something, from nature to Nazca lines. As for their role in the game
>They never vary the route they fly, because their memories of guarding an ancient city remain steadfast. Black dex entry
>The guardians of an ancient city, they use their psychic power to attack enemies that invade their territory. White dex entry
So this along with their basis, means they are kachina spirits of Desert Resort that protect it.
