Full Cuticle (Eponychium) of Fingernail Description
[Continued from above] . . . nail plate together to provide a barrier that’s waterproof. Beneath the eponychium is the membranous pterygium, providing further protection to the skin against bacteria and infection. The eponychium folds over the top of and back in on the lower edge of the epidermal cells at the junction with the nail. Just beyond the cuticle, particularly on the thumb, the nail body may be whitish or lighter in color in a small hemisphere called a lunula.