Epithelium (epi- + thele + -ium) is one of the four basic types of animal tissue. The other three types are connective tissue, muscle tissue and nervous tissue.he lining of the esophagus is an example of a non-keratinized or moist stratified epithelium. Transitional. Transitional epithelia are found in tissues that stretch and it can appear to be stratified cuboidal when the tissue is not stretched or stratified squamous when the organ is distended and the tissue stretches.