Arenicola defodiens, commonly known as the lugworm, is a marine worm that plays a crucial role in the ecosystem of coastal regions. This burrowing species is characterized by its distinctive appearance and unique feeding habits, contributing significantly to the health and productivity of sandy shores.
Description & Characteristics
Arenicola defodiens is a robust, segmented worm with a cylindrical body that can reach a maximum size of approximately 15 centimeters in length. Its body is typically reddish-brown in color, and it possesses a distinct head with a pair of palps and a pair of tentacles. The worm’s body is covered in numerous bristles, known as chaetae, which aid in its movement through the sand.
Habitat and Occurrence
Arenicola defodiens is widely distributed along the Atlantic coast of Europe and the eastern coast of North America. It is a common inhabitant of intertidal and subtidal sandy shores, typically found in the lower intertidal zone and shallow subtidal regions. This worm is particularly abundant in areas with a high density of sand and a moderate wave action. Arenicola defodiens prefers a habitat with a wide range of depths, ranging from the intertidal zone to depths of up to 20 meters. It can be found in various marine zones, including the littoral, neritic, and oceanic zones.
Taxonomy
Arenicola defodiens belongs to the Class Polychaeta, which encompasses a diverse group of marine worms. It falls under the Family Arenicolidae, a family that includes other burrowing worm species known as lugworms.
Feeding
Arenicola defodiens is a deposit feeder, obtaining its food from the sediment it ingests. Its feeding strategy involves burrowing into the sand, creating a U-shaped tunnel with two openings. At the surface, it creates a characteristic cast of sand, marking its presence. The worm then consumes the sand, extracting organic matter, including detritus, algae, and bacteria. The sand, devoid of its nutritive value, is expelled through the other end of the burrow, contributing to the formation of the characteristic sand cast.
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