Snapdragon Pest Identification

Hi, post-heatwave I noticed leaves of our bee balm and snapdragons were translucent. It could be sun/heat damage, but upon closer inspection, there were 2 pests. One's maybe moth/caterpillar larvae? (They move fast.) The other is like a fine black dust... similar to snapdragon/poppy seeds, but finer. Can anyone help? Thanks!

 

The "black dust" is actually the caterpillar-processed parts of the leaves. Frass is the polite term.

As for the caterpillars, they'll be more identifiable in later stages (well, to me, anyway). They go through a number of moults as they grow, with the final one or two moults typically the most colourful (and thus helping to identify). Look into Bt as a relatively safe way to control them if that's your goal: Bacillus thuringiensis - Canada.ca

 

That's incredibly helpful, thank you Daniel! New curse word too. ;)