| Archiacanthocephala, Palaeacanthocephala, Acanthocephala, Echinorhynchus, Seisonidae|Eoacanthocephala Wikipedia
Eoacanthocephala is a class of parasitic worms, within the phylum Acanthocephala. They feed on any aquatic cold-blooded creature such as turtles and fish. Their proboscis spines arranged radially, no protonephridia, persistent ligament sacs in female. The only reliable way to identify the group is that they only have one cement gland. This is a primitive characteristic and hence the name.