The Kradian are a humanoid species. It seems there may be a great variety among the Kradian species. In some cases Ktarians have distinctive foreheads divided into two hemispheres (which seem to be bones), and distinctive yellow eyes with horizontally slitted pupils. In the case of a Kradian/Human hybrid, the resulting offspring can lack the bony forehead structures and yellow eyes, and instead have exo-cranial ridges. A rare complication of these hybrid gestations occur when the baby shifts position in the uterus, and the exo-cranial ridges lodge in the uterine wall.