frontal setae
A C D E F H M N P S T V Z

A pair of setae (Fig.3a.jpg), when present, can be situated dorsally, anteriorly or antero-ventrally to the pupal head, which on the flattened exuviae may be described as being anterior to, between, or posterior to the bases of the antennal sheaths respectively.

Alternative forms for frontal setae : frontal seta, fs.