The discussion on the usefulness of mosquitoes reminds me of a question that has always pestered me - what would happen if mosquitoes became extinct?
Now, the possibility of these spawn from Hell becoming extinct are quite, quite low (unless there’s a major ice age or something). Nevetheless, it never hurts to wish.
So, how much would the world’s ecosystems and human life change if these creatures (to be generous) were extincted?
WRS
Change the first part of the sentence to :“The discussion of the usefulness of cockroaches . . .”
This refers to this thread: http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=184875
WRS
If it ever comes to a vote I think I know how this one will turn out regardless of the consequences. 
Mosquitoes do provide massive quantities of protein for the world bat population. Which is why I don’t mind bats.
Mosquitoes, like it or not, are a good species to have around. They are pollenators. Their larvae are food for many species of fish and amphibians. In addition to being eaten by bats, as the above poster noted, mosquitoes are also a food source of many birds, such as purple martins.
Don’t get me wrong - the mosquito population must be controlled in order to reduce malaria, encephalitus, west nile, etc. infections. But they do play a benefitial purpose overall.
Now FLEAs on the other hand…
…are responsible for controlling ahuge range of species, primarily as disease vectors.
::imagining me pushing button causing extinction of every mosquito on Earth:: 
Back in the 50’s or so, there was a campaign to eliminate malaria by killing all the mosquitoes that carry it, using DDT. This was aborted when the other effects of the DDT were found to be worse than the mosquitoes. I don’t know if anyone thought about what other side-effects there might be from eliminating the mosquitoes.
If mosquitoes became extinct, malaria would suffer.
Arguing for mosquitos is like a post on here recently, about a campaign to save the guinea worm.
We had a previous discussion on this topic, for those who are interested.
I’d be a very happy man, and I’m sure other less HORRIBLE SPAWN FROM HELL insects would soon fill in the niche.
I can dream.