Toothpick fish (Candiru): Candiru is a freshwater fish that belongs to catfish. They are eel-like and almost transparent, making them very difficult to see. This fish has a smooth, mucous skin and gills with barbed spines, making it a powerful and fast swimmer. They live in the Amazon River Basin and are the fish most feared by locals. This fish is a parasitic animal, and their method of survival is as simple as it is cruel: first test the taste of the water and try to find the flow of water coming from the gills. Once it finds a similar current, it will follow the current and swim into the host's gill cover, use the barbs on its head to fix its body in the host's gill cover, and then suck the host's blood. This gives the toothpick fish a "Brazilian" look. "Vampire". Swimming and urinating in Hanoi are taboos for tourists because toothpick fish are attracted to body fluids and quickly burrow into the human body to suck blood and even eat human tissue, causing severe pain. Unless surgery is performed, the toothpick fish will not come out of the human body, and even the locals are frightened by the news. The toothpick fish is a freshwater fish belonging to the catfish family. It is a fish of the order Siluriformes that grows in the Amazon River Basin of South America. It may be the smallest vertebrate in the world. The adult body is less than 10 cm. Its body color is transparent and its body is slender, so it is difficult to be found in the water. It belongs to the class of Hairy-nosed catfish. There are bunches of spines on the gill cover, and they live by parasitism. They usually penetrate into the gills of large fish, hook them with spines, and suck the fish's blood. This fish has a smooth, mucous skin and gills with barb-like spines. It is a powerful and fast swimmer, and it also makes people feel creepy.