鲨鱼,亦称“沙鱼”或“鲛”,属脊椎动物亚门软骨鱼纲鲛目鱼类。鲨鱼在旺盛时期曾达530多种,现存约250种,我国有70余种,鲨鱼是世界上最大的鱼,其中鲸鲨的体长可达25米,体重可达80吨。 Shark, also known as “sand fish” or “鲛”, is a vertebrate subphylum cartilaginous fish fish. There were more than 530 species of sharks during the heyday. There are about 250 species in existence. There are over 70 species in our country. Sharks are the largest fish in the world. Whale sharks can reach 25 meters long and weigh 80 tons.