Pretty sure those glowy things were a bug, and not of the insect variety.
Based off of some extrapolation and guesstimation, the firefly elytron will likely be used in a carpentry synth to create a bow in the low 40s.
(Weevil elytron is used to repair Weevil Bow, which the recipe for is unknown. Based on the way materials are ranked, as well as how items are used in other similar circumstances, it is my humble speculation that the Firefly elytrons will be used as a main ingredient and repair material for the L42ish Firefly Bow. Wow, I'm a nerd.)
I'd just vendor them. Odds are if you need them in the future, you can get them easy enough.