Hi Stan,

Thank you so much for your question!  I had to get some help on this one, so I asked Ann Hazelrigg, PhD.  I am not sure if you are familiar with Ann.  She is the the director of the Plant Diagnostic Clinic and a statewide resource for commercial growers, Master Gardeners, home gardeners and the general public to identify disease, insect and weed samples. 

She did tentatively identify the insect as a lightning bug (pictures were a little unclear) and should be of no concern to your Maple trees.  She requested that you take a look at the factsheet below and see if the markings match, and if they don't, please let us know.  

https://hortnews.extension.iastate.edu/lightningbugs

Hope this helps!