Sandworm

Arenicolidae; lugworm

The common name for the sandworm family of the phylum Annelida, the polychaetes, and the order Microchaetes. Also known as sea worms. For the body is cylindrical large worms, the head is small, trilobate, turn the kiss saccate, the trunk can be divided into 2 ~ 3 body area? Thoracic area without gills, with gills in the abdominal area and?

Sandfly (5 pictures)

Elongated segmented inconspicuous tail area. The warty feet are bilobed. Sand caterpillar is a dominant species on the bottom of mud and sandy beaches in the intertidal and estuarine zones, diving in L-shaped or U-shaped burrows. It swallows large quantities of sediment and digests the organic matter and small animals in it. As a result of constant swallowing, the sediment above the head end of the insect sinks, forming a funnel-shaped opening. There are four genera and nearly 30 species of sand caterpillars in the world. The Brazilian sand caterpillar in China's Yellow Bohai Sea is in its reproductive prime from August to September, with spherical or ovoid gelatinous egg sacks attached to the beach surface where the head is sunken.

Annelida (Annelida) Polychaeta (Polychaeta) sand caterpillar genus (Arenicola) of all marine worms of the general name. Often large in size. Burrows deep in sandy seabeds or intertidal zones. Fishermen use them as bait. Adults of sand caterpillars (e.g., A. marina) off the coast of Europe are about 23 centimeters (9 inches) long. Along the coast of North America, A. cristata is 7.5-30 centimeters (3-12 inches) long. The body is divided into segments, with the head end dark red and the segments behind the head wider and lighter in color. Toward the tail end, the body is thin and yellowish-red. The middle of the body has bristles and about 12 pairs of pinnate gills. Feeds on organic debris, swallowing it along with sand grains. The coiled feces are visible at the mouth of the burrow at low tide. Burrows to a depth of up to 60 centimeters (2 feet). Hermaphroditic. Heterozygous fertilization.