Shokawa ikoi was a 1.8 m long choristoderan diapsid reptile closely resembling and closely related to the smaller choristoderan, Hyphalosaurus. It lived during the Lower Cretaceous in what is now Japan. As with Hyphalosaurus, S. ikoi had an extremely long, thin neck with a small head. The mouth was filled with long teeth used to snare small fish. The generic name refers to the village of Shokawa, located in Gifu Prefecture, Japan, while the specific name honors the collector of the first specimen, one Mr. Ikoi Shibata.