Stratum lucidum


 * For the layer of the hippocampus, see stratum lucidum of hippocampus.

The stratum lucidum (Latin for "clear layer") is a thin, clear layer of dead skin cells in the epidermis, and is named for its translucent appearance under a microscope. It contains a clear substance called eleidin, which eventually becomes keratin. This layer is only found on the soles of the feet and the palms of the hands.It is found beneath the stratum corneum of thick skin, such as that on the palms of the hands and the soles of the feet. The keratinocytes of the stratum lucidum do not feature distinct boundaries and are filled with eleidin, an intermediate form of keratin.

The cells of the stratum lucidum are flattened and contain an oily substance that is thought to be the result of lysosome disintegration. It is this substance that gives the stratum lucidum its waterproof properties, and, thus, it is also called the barrier layer of the skin.