The cercomer is a vestigial structure. This magnification of its posterior end reveals two of the hooks that were present in the hexacanth embryo that initially infected the beetle. Considering that these hooks were about one-half the diameter of the initial hexacanth, the small size of these hooks relative to the cercomer, and particularly to the cysticercoid as a whole, indicates just how much the parasite has grown in the two weeks since the host was first infected.