[matese]

I googled it trying to find a photo of it, then came upon a photo of a Scarlet Lily Beetle. That's what's eating the lilies. I do have the spotted Lanternfly but are not eating flower leaves. Now to see what insecticide kills them.

Scarlet Lily Beetle
(Lilioceris lilii)
If you own Lillies and live in a temperate climate, then you may have encountered this one already.
Scarlet Lily Beetles are a member of the leaf beetle family, of which there are around 37000 (and possibly up to around 50000) separate different species.
To help identify them, they’re bright red – I should probably say scarlet! They’re more elongated than a Ladybug and without spots. Usually around ¼–⅜ in (or 6 to 9 mm) in length, with relatively long legs. Unlike the similar cardinal beetles, these have a more dimpelled elytra.
They winter in the soil, emerging in Spring. Found throughout much of Asia, Europe and North America, preferring cool and moist climate.
They lay their eggs on the underside of leaves, around 7-14 days later the eggs produce yellow, orange or brown larvae. After almost a month of feeding on the plant, they burrow into the soil for the pupation stage – for around 20 days before emerging as adults and continuing their eating.