Pectinaria (annelid)

Pectinaria is a genus of marine polychaete worms belonging to the family Pectinariidae, commonly known as ice cream cone worms or trumpet worms. These worms are characterized by their distinctive conical tubes constructed from carefully selected sand grains or shell fragments, cemented together with mucus secreted by the worm.

The worms themselves possess a body divided into segments, with specialized structures for feeding and tube construction. The anterior end features a pair of golden-colored, comb-like structures called paleae, which are used for digging and gathering sediment. These paleae are a defining feature of the family Pectinariidae and are used in locomotion and tube construction.

Pectinaria species are typically found in sandy or muddy substrates in shallow coastal waters, although some species can inhabit deeper environments. They are deposit feeders, extracting organic matter from the sediment. The worms live within their self-made tubes, extending their paleae to collect food particles from the surrounding environment.

The tubes of Pectinaria are open at both ends, allowing for water circulation and waste removal. The wider end of the tube is usually buried in the substrate, while the narrower end projects above the surface. The size and shape of the tube vary depending on the species and the availability of suitable building materials.

These worms play a role in benthic ecosystems by bioturbating the sediment, influencing nutrient cycling, and serving as a food source for other marine organisms. Several species are used as indicator species for environmental monitoring due to their sensitivity to pollution.