Tissue-feeding ectoparasites often graze on sloughed epithelium or mucus from the host. However, they may use mechanical or chemical means to erode living tissue and ingest it.
Monogeneans have a mouth (M) and may secrete proteases to digest host tissue. The material is then pumped in by the pharynx. The prohaptor (P) may contain adhesive glands that assist in positioning the mouth during feeding.
Chewing lice use mandibles (M) to ingest host skin.
