Late comer to be he party here, I hope this don't fall under thread necromancy. Anyway, In my view of aldryamic stuff insects actually are a kind of plants. Butterflies are moblile flowers, ants are mobile root noodes transporting nutriets to the roots etc etc Which to me makes it totally acceptable with inectile looking aldryami. (And there is a story there about Gorakkiki and Kyger Litor in there ....)
In general I tries in my world-building efforts break free from real world explanatory concepts, and see similarities as more like percived parallel evolution than factual identical entities (a result of early exposure to Glorantha I guess). Of course it has to be balanced towards making the world too alien for people to enjoy playing in.
So, I have little problem with Giger and body snatchers, in fact I have a fairly long write up about an alternative elven plant based biology (geared towards 5e, but actual systemless hmmm ... perhaps I should look it over again and glorantha-ish it).