part of part of composed primarily of keratinocyte skin epidermis stratum corneum of epidermis stratum granulosum of epidermis stratum lucidum of epidermis Located between the stratum granulosum and stratum corneum layers, it is composed of three to five layers of dead, flattened keratinocytes. The keratinocytes of the stratum lucidum do not feature distinct boundaries and are filled with eleidin, an intermediate form of keratin. integumentary system layer