
Anopheles gambiae female bloodfeeding
As you can see at the back of the abdomen, the big drop of "blood", is in fact not coming from a previous bite. The female Anopheles, during it's feeding time, is removing the plasma (bearing some intact erythrocytes, hence the red colour) from the blood she is taking.

The "Anopheles gambiae" complex consists of at least seven morphologically indistinguishable species of mosquitoes in the genus "Anopheles". The complex was recognised in the 1960s and includes the most important vectors of malaria in sub-Saharan Africa, particularly of the most dangerous malaria parasite, "Plasmodium falciparum".