Q.Do you know what this bug is?
This year these bugs are all over my dahlias and the leaves are turning brown. I have many buds but a lot of them are dying before maturing. Are these bugs responsible? If so, what do I do? I know it’s probably too late for this year, but I’d like to prevent the same thing from happening next year. I’ve never had this problem before. I’m near Toronto in Canada and we have had a hot, dry summer.

Certified GKH Gardening Expert
It looks like a type of beetle which is not listed as a common threat to dahlias. I've included the most common bugs and diseases of dahlias below.
https://www.gardeningknowhow.com/ornamental/bulbs/dahlia/dahlia-care-grow-dahlia-plant.htm
https://www.gardeningknowhow.com/ornamental/bulbs/dahlia/dahlia-pests-and-diseases.htm
https://www.gardeningknowhow.com/ornamental/bulbs/dahlia/bugs-on-dahlia-plants.htm
https://www.gardeningknowhow.com/plant-problems/pests/insects/japanese-beetles.htm