The most anterolateral seta in the series of setae (maximally consisting of seven pairs, seta 2- to 8-C) occurring on the dorsal apotome, just posterior to the median labral plate; well developed in anophelines; in culicines, sometimes arising from underside the head; in Sabethini and Toxorhynchites, associated with seta 0-C on the median labral plate; interpreted as being absent along with seta 2-C when two of the seven pairs of this series are missing.
Larval chaetotaxy: seta 3-C