[pvaldes]

> I've never seen anything that included mosquitoes as anything but a disease vector,

There are entire branches of ecology studying (among other things) the role of mosquitoes in ecosystems. Limnology for example.

> I've heard numerous opinions saying that mosquitoes are the one class of animal whose absence would not be noticed by the ecosystem

Define "numerous"

I can't understand how somebody could claim that nothing will occur if we wipe an entire "class" of animals comprising more than 3000 species and that are linked with almost all in freshwater ecosystems in its quadruple role of prey, predator, pollinisator and vector. Hundred of species of vertebrates of economic interest to man depend on them, probably.