Fukuisaurus (meaning "Fukui Prefecture lizard") is a genus of herbivore Ornithopoda dinosaur that lived during the Early Cretaceous in what is now Japan. The type species is F. tetoriensis, which was named and described in 2003.
Discovery and naming
Remains of
Fukuisaurus were discovered in 1989, in Katsuyama, Fukui Prefecture, in rocks from the Kitadani Formation, dating to the
Barremian. The
type species,
Fukuisaurus tetoriensis, was described in 2003 by Yoshitsugu Kobayashi and
Yoichi Azuma. The genus name refers to Fukui; the specific name to the geological
Tetori Group. The
or cotypes are FPDM-V-40-1, a right maxilla, and FPDM-V-40-2, a right jugal. Further elements of a skull and a right sternal plate had been recovered.
[Kobayashi, Y. and Azuma, Y. (2003). "A new iguanodontian (Dinosauria; Ornithopoda), form the lower Cretaceous Kitadani Formation of Fukui Prefecture, Japan". Journal of Vertebrate Paleontology 23(1): 166-175] Since 2003 much more extensive finds have been made and much of the skeleton is now known.
Description
Fukuisaurus was a relatively small ornithopod. In 2010 Gregory S. Paul estimated its length at 4.5 meters and its weight at 400 kg.
[Paul, G.S., 2010, The Princeton Field Guide to Dinosaurs, Princeton University Press p. 286] Being a bipedal, optionally quadrupedal, animal, it was similar in general build to
Iguanodon,
Ouranosaurus and
Altirhinus. According to the describers
Fukuisaurus was exceptional in that its skull was not kinetic: the tooth-bearing
maxilla would be so strongly fused to the
vomer that a sideways chewing motion would have been impossible.
Classification
Fukuisaurus was assigned by its describers to
Iguanodontia, although the presence of a posterolateral process of the sternum indicated that it likely also belongs to
Styracosterna. Their
cladistic analysis showed that
Fukuisaurus was more derived than
Iguanodon and
Ouranosaurus, but less derived than
Altirhinus.
RamÃrez-Velasco
et al. (2012) found
Fukuisaurus to be a basal member of
Hadrosauroidea,
while Bertozzo
et al. (2017) recovered it as a non-hadrosauroid styracostern.
