Dear Said,

Though I have never done PCRs for Mosquitos, I have good experience in subtyping and identification of mouse strains using simple and rapid PCRs. But the basics are always same. You need a general positive control that is common between them (A common gene) and a unique gene or sequence for each of your species, which can be used for the differentiation. I hope a good amount of sequence data is available for these species to identify unique sequences to differentiate them properly. You just need to design primers and do the PCR. However, I found some literature regarding the same. I hope this should be helpful to you. Goodluck.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4863023/

You can do PCR but you need specific and broad primers for this one way is to get sequence which might be a tedious   task. other ways to find the specific primers on virtual libraries and use them (you have to standardize all protocols if some researcher have done the same earlier use the protocol modify according to the setup you have to obtain results 

You can contact Jenny Hesson ([email protected]) who has been working with Culex mosquitoes. Maybe she can help you.