Priapulus
Priapulus is a genus of marine worms belonging to the phylum Priapulida. These worms are commonly known as penis worms due to their distinctive phallic shape, a characteristic that has led to their classification as a separate phylum.
Characteristics
Priapulus worms are characterized by their elongated, cylindrical bodies, which typically range in size from a few centimeters to several inches in length. They have a distinct proboscis at the anterior end, which is used for capturing prey. The proboscis is covered in spines and can be retracted into the body when not in use.
Priapulus worms lack segmentation and have a simple, unspecialized body cavity. Their digestive system is complete, with a mouth at the anterior end and an anus at the posterior end. They also possess a pair of retractable, spiny claws at the posterior end, which are used for locomotion and anchoring.
Environment
Priapulus worms are primarily found in marine environments, typically inhabiting soft sediments in intertidal zones and the deep sea. They are often found buried in the sediment, extending their proboscis out to capture prey.