Factual error: The plot is about a mosquito who stung the murderer. Although Gary Sinise mentions (correctly) that only female mosquitoes bite, the one caught alive on the table is a male mosquito (look at its bushy antennae and abdomen which is thin and definitely deflated). All mosquitoes used in the episode are male.
Other mistake: Hawks is handed a pretty small container with some of the victims brains in it, and says there is about 50% of the brain still left out there to find. There is no way half of a brain is in that small container, it's not even filled all the way.