Biting nails can lead to broken skin on the cuticle. Occasionally infection occurs on the toes or on the nail cuticle. The nail plate is generated by the nail matrix located just under the cuticle. This serosa secretes a cuticle rich in chitin that protects the embryo against desiccation. Each strand of hair is made up of the medulla, cortex, and cuticle. In crustaceans, there is a second oxidase activity leading to cuticle pigmentation. Nematomorphs possess an external cuticle without cilia. The enzyme chitinase produced in the stomach helps digest the chitinous cuticle of arthropod prey. Mycelia develop on the underside of the leaf cuticle and lesions appear. The body is segmented and covered in a chitinous cuticle. All pigments wash out of the cuticle. This cleans the shell, but erodes its cuticle. They can often fly immediately after breaking from their pupal cuticle. Campaniform sensilla are cap-shaped protrusions located on the surface of the exoskeleton (cuticle) of insects. Each body segment and limb section is encased in hardened cuticle.