The ridge that extends along the anterior margin of female T9 and receives the site of origin of the ventral and the dorsalT9-second valvifer muscles.
written by: Ernst, A., I. Mikó, and A. R. Deans. 2013. Morphology and function of the ovipositor mechanism in Ceraphronoidea (Hymenoptera: Apocrita). Journal of Hymenoptera Research.