Ruby-throated hummingbird (Archilochus colubris)
NC State Extension Gardener Plant Toolbox lists the garden petunia’s flowers as providing nectar for hummingbirds; the deep funnel-shaped corolla suits the ruby-throated hummingbird’s long bill.
Hawkmoths (Sphingidae (family-level entry))
Petunia inherits a moth-pollination syndrome from its wild parent Petunia axillaris (pale, fragrant, long-tubed, evening-scented flowers). Pale fragrant garden cultivars retain that scent and are visited by night-flying hawkmoths, though modern bedding hybrids vary widely.