There is a centriolar complex within implantation fossa which depresses in the middle of the hind nucleus.Centriolar complex consists of proximal centriole, intercentriolar body and basal body.

• 核后端正中有凹陷入核内的植入窝，中心粒复合体位于植入窝内，由近端中心粒、中心粒间体和基体组成；