Yaverlandia (meaning "of Yaverland Point/Yaverland Battery") is a genus of maniraptoran dinosaur. Known from a partial fossil skull (MIWG 1530) found in Lower Cretaceous strata of the Wessex Formation (Upper Silty Bed; Vectis Formation) on the Isle of Wight.[1][2][3] it was described as the earliest known member of the pachycephalosaurid family, but research by Darren Naish shows it to have actually been a theropod, seemingly a maniraptoran.[4] The type species is Y. bitholus.[5]
| Yaverlandia Temporal range: Early Cretaceous, | |
|---|---|
 | |
| Replica of MIWG 1530 seen from two different angles | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | Theropoda |
| Clade: | Maniraptoriformes |
| Clade: | Maniraptora |
| Genus: | †Yaverlandia Galton, 1971 |
| Species: | †Y. bitholus |
| Binomial name | |
| †Yaverlandia bitholus Galton, 1971 | |
Discovery and naming
MIWG 1530, the holotype skull, was discovered in 1930, in England and were commented upon by Watson (1930).[6][7] It was referred to as an iguanodontid of the genus Vectisaurus in 1936.[8] When Steel (1969) followed Hulke (1879)[9] in listing Vectisaurus as an iguanodontid, Peter Malcolm Galton (1971) named the fossil as Yaverlandia, which he described as a pachycephalosaurid since the skull of Yaverlandia was different than that of Vectisaurus (Mantellisaurus).[5]
In 2012 additional remains were reported, but these have not been described.[10]
Description
Yaverlandia was about 3 ft (1 m) in length and 1 ft (30 cm) in height.[11]
Classification
Before being named, Swinton (1936) had MIWG 1530 placed within Mantellisaurus,[8] which was a member of the Iguanodontidae. Galton (1971) upon describing Yaverlandia placed it within the Pachycephalosauridae.[5] Sullivan (2000), Sereno (2000)[12] Naish (2006; unpublished thesis), Sullivan (2006)[13] and Naish (2008)[4] all re-classified Yaverlandia as a maniraptoran.
Paleoecology
Yaverlandia was found in the Vectis Formation and it would have coexisted with the nodosaur Polacanthus,[14] the neornithischian Hypsilophodon,[14] the iguanodontid Mantellisaurus,[14] an indeterminate euornithopod,[14] the spinosaur Baryonyx,[15] the dromaeosaurid Vectiraptor,[14] the plesiosaur Vectocleidus pastorum[16] and the crocodylomorph Hylaeochampsa vectiana.[17]
