Fucanlong is a genus of extinct marine reptiles, specifically a group of ichthyosaurs, that lived during the Mesozoic Era. Fossils of Fucanlong have been found in China, providing insights into the diversity and evolution of ichthyosaurs during the Late Jurassic period. These creatures are characterized by their streamlined bodies and adaptations for life in the ocean, resembling modern dolphins in appearance. Their discovery contributes to our understanding of prehistoric marine ecosystems.