What is "dinodocus"

Dinodocus (meaning "terrible beam") is the name of a genus of sauropod dinosaur, named by Richard Owen in 1884. The name is now usually considered a nomen dubium. The only species, D. mackesoni, a name given to some fossil limb bones from the Lower Greensand (Lower Cretaceous) of Kent, England, was formerly placed in the genus Pelorosaurus ( Mantell, 1850), but review by Upchurch et al. (2004) concludes that Dinodocus is a nomen dubium.