Eelarvgus

Eelarvgus is a genus of ribbon worms in the phylum Nemertea. It comprises several described species known for their eel-like bodies and predatory habits. The group is characterized by slender, soft-bodied forms with a smooth integument and a distinctive proboscis apparatus typical of nemerteans.

Description and morphology: Members are elongated, ribbon- or worm-like and usually pale to brown in color, with body lengths ranging from a few centimeters to several tens of centimeters in the largest species. They lack true segmentation and possess a eversible proboscis used to capture prey. The head region is not greatly differentiated from the trunk, reflecting their soft-bodied body plan.

Distribution and habitat: Eelarvgus species inhabit temperate and tropical coastal waters worldwide, often found buried in sand or mud, under rocks, or among seagrass and macroalgae. They occur from the intertidal zone down to shallow subtidal depths and tolerate a range of sediment types.

Diet and behavior: These worms are carnivorous, feeding on small invertebrates such as crustaceans and polychaetes. Prey capture relies on rapid eversion of the proboscis, which delivers immobilizing secretions and helps seize prey before ingestion.

Reproduction and life cycle: Reproduction is sexual, with fertilization occurring in the water column in many species. Larval development varies among species, with some exhibiting indirect development and others showing direct development.

Taxonomy and naming: The genus name Eelarvgus combines an eel-like form with a distinctive taxonomic suffix chosen to reflect its relationship to related nemertean genera.

Conservation and significance: The genus has not been widely evaluated for conservation status. As soft-bodied, sediment-dwelling invertebrates, they can be sensitive to habitat disturbance, but they also offer value in comparative studies of morphology and predation strategies within Nemertea.