#5
Simulium have the basal r cell about 1/4 wing length (longer in other genera) and basal m cell absent (usually present but hard to see in other genera). About half of the subgenera have bands on legs or thorax. There are other characters but br length and color pattern are most easily seen. The color pattern with thorax unmarked and basal 2/3 of tibiae yellow suggests subgenus
Eusimulium (= Simulium aureum species group) but I'm not sure.