"Horseshoe crab worm" is pronounced "hòu chóng". Horseshoe crab worms are introduced as follows:

Horseshoe crabs, also known as horseshoe crabs, are ancient arthropods that are not true crabs, but a separate group of organisms. Horseshoe crabs are found in the oceans, mainly along the coasts of North America, Asia, and Europe. Horseshoe crabs have a hard-shelled exoskeleton that is bluish-gray or brown in color, and have a long tail and a crustacean-shaped head cap.

Their body structure is so primitive and virtually unchanged from the time of the dinosaurs that they are considered living fossils. Horseshoe crab worms usually live in shallow waters and feed on mollusks, worms and small invertebrates. They gather on beaches during the breeding season to mate and lay eggs.

The blood of horseshoe crab worms contains a substance called hemolysin, which is used in the manufacture of drugs and medical devices for testing. Conservation of horseshoe crab worms has become a focus of concern in many areas due to their environmental sensitivity and ecological importance. Horseshoe crab worms are considered to be an indicator species for biodiversity, and their presence is important for maintaining the balance of marine ecosystems.

Characteristics of Horseshoe Crab Worms

1. External structure: Horseshoe crab worms have hard exoskeletons, which are bluish-gray or brownish in color and are shaped like horseshoes, hence the name horseshoe crab. Their body is divided into a cephalothorax and a tail, and the cephalothorax has a crustacean-shaped head cap.

2. Longevity and antiquity: Horseshoe crabs are considered living fossils and have existed for more than 400 million years with little change in their external structure. They are one of the oldest and most primitive creatures on earth.

3. Living environment: Horseshoe crab worms mainly inhabit shallow water areas, such as sandy beaches, estuaries and bays. They like to dig holes in the sandy or muddy seabed to live and feed on mollusks, worms and small invertebrates on the seabed.

4. Breeding behavior: Horseshoe crab worms will gather on the beach to mate and lay eggs during the breeding season. Female horseshoe crabs dig holes and lay thousands of eggs, while males release sperm around them. After the eggs hatch, the young horseshoe crabs go through several developmental stages and take a long time to mature.

5. Indicator of biodiversity: Horseshoe crab worms are regarded as an indicator species of biodiversity, and their presence plays an important role in maintaining the balance of the marine ecosystem. They provide a food source for other organisms and contribute to sediment circulation by breaking up the seafloor surface as they search for food on the beach.

6. Blood Properties: The blood of horseshoe crab worms is blue in color and contains a substance called hemolysin. Hemolysin is used in the manufacture of drugs and medical devices for testing, and has functions such as antibacterial and anticoagulant.