
Anopholes mosquito showing position of proboscis in line with body.

Unidentified mosquito showing typical perpendicular position of proboscis of non-Anopholes mosquitoes.
Only Anopholes mosquitoes transmitt malaria and they are easy to identify by the position of the proboscis in relation to the body. Notice also that the body of the Anopholes mosquito is held at an angle to the skin when biting, whereas in other mosquitoes the body is more or less parallel to the skin; however, sometimes the hair on your skin prevents a parallel position, so to be sure observe that the proboscis of the Anopholes is in line with its body. See the above captions.
Camping in Florida this November, I was surprised to see Anopholes mosquitoes attempting to bite me. Whether they were the species that transmitt malaria is unknown, but in 2003 there were eight cases of malaria that originated in Palm Beach County, Florida. However, the malaria transmitted was the less severe species of the disease parasite.
I don't think there's any reason to be concerned, but if you live in Florida or are camping there you might be on the lookout for the Anopholes mosquito and swat them if they land on you. This may sound odd to you, but most Florida mosquito bites produce no reaction in me, so I usually don't bother swatting them—and I think I've already had West Nile—but Anopholes are somewhat worrysome.