Features of Acanthocephalan Hooks Using Dual Beam Preparation and XEDS Phase Maps

Acanthocephala is a minor phylum of dioecious worms (Helminths) which is often overlooked in beginning biology and parasitology courses [1]. Hooks are a major characteristic of all known species, thus they have been referred to as thorny headed or spiny headed worms. An evertable (protrudible) proboscis is armed with the hooks which provide permanent attachment to the host intestine. Over 1150 species have been described with new ones listed each year. Phylogenetically, based on DNA studies, their nearest relatives are not other worms (nematodes, cestodes) but rotifers. They range in size from microscopic to 65 mm. Fish and birds are common hosts while only eight species have been isolated from humans to date [2].