The fellow you see here is the Type Specimen for the species and he lives on display in the Yorkshire Museum. As the reference specimen for the species, all hopeful specimens that may belong to this species are checked against the Type Specimen to see if they share diagnostic features.
The Yorkshire Museum was given this important ichthyosaur fossil back in 1857, albeit in bits and pieces. The first bits of fossil bones were found near Whitby on the North Yorkshire coast by workmen quarrying alum. They recognized the bones as belonging to a fossilized reptile and alerted local authorities who in turn alerted the good Master Owen.
It was quite an undertaking to recover as it was found in more than fifty pieces in massive shale blocks and the alum quarry was active at the time. Alum quarrying helped share the Yorkshire Coast as an important staple of the textile industry going back to the 16th-century. By the 1860s, alum quarrying was slowing down. The ability to manufacture synthetic alum by 1855 had shifted the industry and it died out entirely by 1871. Lucky for us, the last years of alum production gifted us this well-preserved eight-metre specimen, one of the largest ichthyosaurs ever discovered in the UK.