Wednesday, December 30, 2015

The Giving of December. Ultrasaurus

    Due to the incomplete nature of the holotype fossils,‭ ‬Ultrasaurus is today seen as a dubious genus of sauropod dinosaur,‭ ‬given that it would be near impossible to attribute further remains to the genus.‭ ‬Ultrasaurus is actually more‭ ‬famous for forcing a naming change in a North American genus of diplodocid dinosaur.‭ ‬In‭ ‬1985‭ ‬the palaeontologist James A.‭ ‬Jenson named three new sauropods from fossils recovered from the North American Morrison Formation.‭ ‬Unaware of Kim’s description of a South Korean sauropod in‭ ‬1993,‭ ‬Jenson named one of his sauropods Ultrasaurus macintoshi.‭ ‬Because Kim named his sauropod first,‭ ‬his description had naming priority,‭ ‬and in‭ ‬1991‭ ‬Ultrasaurus macintoshi was renamed Ultrasauros macintoshi.‭ ‬This is now a moot point however as after this Ultrasauros was discovered to be a fossil chimera composed of diplodocid and brachiosaurid‭ (‬in fact probably Brachiosaurus‭) ‬fossils.‭ ‬On top of this the holotype fossil‭ ‬of Ultrasauros,‭ ‬a single vertebra was identified as not only belonging to another one of Jenson’s‭ ‬1985‭ ‬sauropods named Supersaurus,‭ ‬but actually belonging to the same individual Supersaurus that made up the holotype,‭ ‬making Ultrasauros a synonym to Supersaurus.
       Back to the South Korean,‭ ‬Ultrasaurus there is speculation that this too may be synonymous with another sauropod genus,‭ ‬yet again,‭ ‬because of the indeterminate nature of the fossils,‭ ‬it is uncertain to prove.

No comments: