hypaxial

hypaxial Any structure morphologically ventral to the chordal axis;

任何形态结构位于脊索部；

upper postventral margin In the caudal fin, the upper part of the postventral margin of the hypaxial web, from the posterior notch to the subterminal notch.

后边缘在尾鳍，后边缘部，从后面凹槽到接近端位凹槽。