Great South Bay Giant Horseshoe Crab

The Great South Bay Giant Horseshoe Crab is a cryptid rooted in Long Island maritime lore, with fishermen claiming to see armored forms as wide as small boats crawling along shallow bay floors. Tales describe them as ancient monsters, their barnacle-crusted shells big enough to capsize a careless dinghy if startled. Most marine experts believe these stories stem from genuine encounters with large, old horseshoe crabs viewed under poor conditions or exaggerated by the fog of memory and local bragging. Yet the persistence of these tales speaks to the primeval eeriness of horseshoe crabs themselves—living fossils that haven’t changed significantly in hundreds of millions of years. The legend serves as a reminder that even thoroughly studied species can still inspire outsized fears and speculative tales when glimpsed under moonlit waters.