SEM Study of Hooks in the Acanthocephala with Emphasis on Structural-Functional Relationships

The retractable proboscis of acanthocephalans is equipped with hooks for attachment to the intestine definitive host. Throughout their evolutionary history, have developed a variety ways maximize anchoring host gut and avoid dislodgement. Hooks vary in size shape along longitudinal axis proboscis, texture, structure, hardness as well contribution absorption nutrients. also chemical composition, especially calcium, phosphorus, sulfur, contributing hardness. Hook roots are paramount them cuticular subcuticular layers proboscis. Roots often simple directed posteriorly but anterior manubria or may be vestigial absent posteriorly. core layer usually continuous that hook. often, not always, maintain similar pattern families. Because inconsistencies inadequacies description hooks, line drawings, various groups acanthocephalans, we decided provide largest assortment morphological anatomical variabilities among many species studied over years. We are, thus, reporting SEM 30 selected 13 families an attempt elucidate patterns trends characteristic acanthocephalan