hypural

hypural notch The crease formed when the caudal fin is bent or flexed.

尾下凹槽当尾鳍或的时候，形成的摺痕。

hypural bones The fan-shaped series of bones (sometimes fused to one or two plate-like bones) to which the caudal fin rays are attached.

尾下尾鳍鳍条附的扇形成列硬(有时融合成一或二个板状硬)。